I make a very comfortable living, wife stays home, we have no debt and I work around 20 hours a week most weeks. Most of my clients are on retainer and I do good work for them. We rarely talk about what "stack" we're using but we always talk about the problems they're trying to solve.
Most of these arguments are about ego, someone being right and wrong and what tools are the best. From an old fart I can tell you this... tools are only as good as the person using them. If you are a shit developer, nothing is going to save you from yourself.
It really seems to me like a huge issue these days is that people can't even stick with a framework or language long enough to ever be decently good at it. This seems to be due in part to your #1 - learning what is needed to get a job and #2 - fear of building a product on the "wrong" stack when they scale to billions of users in 2 weeks (hint: this doesn't happen).
The biggest lesson I've learned from building a product is that no matter what tool you are using, you cannot engineer your way out of a marketing problem. No marketing = no success. There is a lot of horribly coded garbage out there making people tons of money because of marketing.
Even with those experiences I would never say there's a correlation between chosen language and success, because in all those cases it was the core business idea that was the driver of success or failure.
I do still try to choose the right tool for the job based on some kind of instinct and experience anyway.
Also, congrats on your gig. From where I'm standing (an old fart still grinding it out at startup #7) that sounds totally awesome. This is going to be my last startup though, I was going to accept my fate and go work for some BigCo before it's too late otherwise I'll have no retirement at all. But if I could find a nice niche like that, I'd happily work part time forever.
I will also add that I am mostly a PHP dev and I do not work with WordPress at all. There is a LOT of work out there, though.
You could also easily get into contracting or freelance development too, since many companies don't really care what tech a developer/team uses so long as the work gets done.
2. But this is definitely true. Additionally, your average Joe doesn't care about the tech you use. They care about what the product actually does, and if works well...they won't care if it's React or jQuery (or whatever).
I think it's an unfair over-generalization. There are quite a few places that started building their tech a fair number of years ago, and have accumulated quite a legacy that needs to be maintained. They would probably want someone with decent knowledge of those dated technologies. The question is, given the choice, would you, personally, want to work on a legacy system, or would you rather prefer to work with something new and shiny. I think the answer will overwhelmingly be the latter. I personally am sure I would pick new and shiny, because it is generally much more pleasant and satisfying to work with than old technologies.
I prefer not to be on the bleeding edge of stuff, especially not in the JS world - got bitten too often by incomplete, missing or flat out wrong official documentation, horrenduous bugs, incompatibilities and sudden breaking changes all over the place.
Side note to all shiny tool vendors out there, if you want people to try out your stuff, provide usable documentation and don't force your users to copy-and-paste from StackOverflow...
Yeah, webpack was definitely the worst offender I remember. How many days were lost in trying to get it to behave... sigh.
1. If you want to get hired, you need to know the tools in fashion now. It's always been like that but recently these proliferated so much it's quite difficult to catch up even in the market you specialize in.
2. If you want to build a successful product, you need to be smart and use what you know in the best way, and only spent your time to learn something new if it's really necessary. That's why some of the biggest sites in the world were written in PHP, Photoshop was originally written in Pascal, Minecraft in Java etc.
There is much more to say about it but the essence is that.