Though that's why it's hard. Just like eating healthy and exercise isn't hard, just requires dedication, yet notice how few people have a particularly good looking body.
The opportunity cost of learning a language is also immense. I've spent an incredible amount of time listening to and reading Spanish. It just isn't for everybody. It has to be something that makes you happy.
Unless you have extended family or somehow became smitten with a foreign country, I am almost certain this is the case. So any attempts are really halfhearted and very little progress is made because the commitment is so large.
This is why, if I ever get around to learning a second language, it will be Esperanto. It takes an order of magnitude of less time to learn and gives you the accomplishment of knowing another language. (Plus uniformity in language is cool.)
Your opinion is a pretty localized one. For many people learning a second language is not an option, it is a must. I would have a very hard time functioning in my field without access to a second language.
You can make do with less, but it's probably going to have an impact on your career, at some point.
The first is whether you speak articulately about complex topics. This one is easy to do from home; reading books, listening to podcasts, and talking with language partners on iTalki will all help get you there.
The second is informal, everyday communication. This one's definitely a struggle. Not only is it hard to pick up on your own, but I'm pretty sure that, even if you've spent some time in a region that speaks the language, there's still no great way to avoid steadily losing it if you ever leave. TV, especially sitcoms, helps, but only a little. There's just not a whole lot of overlap between the things people actually chatter about all day, and the things that make for interesting entertainment.
That applies even to your original language. ~15 years after moving away, talking to family and friends at home feels... awkward. I can still do it easily, but honestly, sometimes I wish I could use English, even if that's not perfect either.
It's so much easier with friends who also moved out. We can switch to a more comfortable language for each thought or even mid sentence if you prefer a specific word choice.
If I have a half an hour conversation, there might be one word that a normal person should know, but that I've forgotten. Comes as a bit of a shock to me when this happens.
On the other hand, the latter probably can't be done at home. While it isn't necessary to be very, very strong in French, without that immersion experience I think you'll never feel "at home" among francophones until you put in the necessary hours into hanging out in French.
Despite this, having the latter is certainly very useful and allows you to get your point across in the vast majority of situations, so if it's the best you can do, it's still worth it if you really want to learn the language.
I think getting C1/C2 certification doesn't really test for that kind of thing, but instead, to my knowledge, being able to communicate increasingly complex ideas in a relatively sterile environment. So, you probably could get fairly automatic when debating about economics or having general conversation or something abstract at home, but in France you probably won't be automatic until you spend a sufficient amount of time practicing all the little things in daily life. This is something I will struggle with to unless I immerse myself someday, but being able to say what you want generally is definitely good enough to at least survive at live decently well. Good luck, sounds like what you're doing is the best possible!
Like most skills, language proficiency work in steps, and you are usually only able to see the next step, the rest goes above your head.
In the case of language, the first step is learning the words and grammar. This can be tested. But there is a whole world beyond that. I realized it when talking about the Japanese language with a girl she didn't even talk about things that come up in tests, like vocabulary. Instead she talked about how to talk to different kind of people, idiomatic expressions, how to convey emotions, even the quirks of writing text messages. She was on the next level, the part about describing things was already a given, not something worth talking about. There are certainly many things lying beyond that, maybe accent, body language, a point where the distinction between language and culture starts to blur...
An interesting thing is that AFAIK, there are no tests that evaluate the proper use of "bad" language. French (my native language) is famous for its colorful swearing. And you can't really call yourself fluent if you don't know how to do it. Proper use of casual and even offensive language, is, I think, an important skill that most foreigners lack, in any language, and yet, most test don't go below business level speech.
It is when you think in this language. Yes. Exactly. You need to become fluent in thinking in a language to be fluent in real life situations.
And its also kinda cool to be able to think in two language. Its kind of a superpower :)
There are 8760 hours in a year. Even if you somehow managed to learn a word an hour, that's still multiple years to get to 20-40k words.
I think we take for granted how many years it takes for kids to learn a language to adult level when we say "kids have an easy time learning languages". It may be easy in that it doesn't require as much conscious study as adults do, but it isn't quick either. Granted mental maturation messes up the time lines, but I think it's hard to argue that it doesn't still take many years.
So depending on what motivates you the time commitment needed at a minimum can be heartening (I'm taking years because there's lots to learn) or disheartening (This is a multi-year endeavor that I'll have to focus on when I could be doing something else).
EDIT: Though reading up on what B2 is, it is a much less daunting proposition, but even C2 doesn't sound like native speaker level, just able to communicate effectively level.
Today, except for pronunciation, I would consider myself fluent, though of course not native. While I do use English daily, I have never worked in an English-speaking country until well after I became fluent. The one thing that made it click was watching a lot of video content without subtitles
I honestly don't get how people talk in noisy bars and restaurants. I struggle even in English. One almost has to shout in the other person's ear. If it's that close I am thinking more about how my breath smells after having a few drinks rather than topic of discussion - lol.
I can tell you from personal experience that it's most important that you speak the language. Get yourself in conversations where you are forced to speak and listen to the language. There's a big advantage to recall words when you need them and to try to understand what the other person is telling you. The stress of the situation will burn the words into your memory. Ultimately you will have no choice but to learn it. Also, even fluent speakers will lose fluency if you don't practice so there's no such thing as being fluent for life without using the language regularly.
The biggest disservice you can do to a person that's trying to learn a new language is to translate for them in their native language. It helps at the moment but long term it's harder for them to learn the new language.
I believe there's a difference between "competence" (I know how to say X) and "fluidity" (I can say X as easily as breathing).
You can learn the first on your own. Takes a lot of effort, sure, but it's doable.
I don't think you can learn fluidity outside of actually living in a country. You need to be bombarded daily with questions that you're forced to respond to. Even then, some people just don't make the effort, which is why you get people who have lived in a foreign country for decades and their language skills haven't improved.
My first three months in China were worth more than the preceding three years of self-study.
You can learn fluidity on your own, but it takes the right kind of practice. It's easy to think of learning a language as "study". You go through books learning words, phrases, verb endings etc. Most exercises in textbooks only care about you getting the right answer, not how quickly you do it.
Compare this to learning a musical instrument. There is some study needed, but realtime practice is the bulk of what you do. If you need 30 seconds to work out the next chord in a song then you can't play the piano. The gold standard is practicing with a metronome. The areas where you can't keep up are the areas where you need to practice.
I'm quite surprised that this idea of realtime practice is still so uncommon even though everyone has a smartphone nowadays. In the past, Pimsleur language courses put an emphasis on being able to answer in the language you are studying more or less straightaway.
Getting to a solid level of competency in a language actually is not that hard. It just requires dedication and consistent practice.
That said, native speakers operate on a different level entirely. In my recent visit to Barcelona, I had no problems asking for directions, talking to the hotel staff and people in bars, chatting it up with friends in Spanish, etc. However, walking into a noisy / crowded restaurant where the language is going 100 miles an hour is a totally different scenario.
As much as I want to believe otherwise, I'm of the opinion that getting to a level of "automatic" response where you can fluidly handle any situation requires living in a country where the language is in your face all day every day--and even then it still takes real effort.
A friend of mine, who's a US ex-pat living in Madrid is of the same opinion. After three years living there, he still doesn't feel 100% confident; although, he admits that he has spent most of his social time around English speakers.
None of this is intended to discourage anyone at all. In fact, learning Spanish ranks as one of the best decisions I've ever made; however, I think it's important for folks to go in with realistic expectations, as there's big difference between functional competency--with a language and fluency with fluency being a "white whale".