This is why you should only make stuff that you want for yourself. The second you get caught up in making money and comparing yourself its now work and good luck sticking with it.
I always turn this around and think what i don't like about the big successful games. Then once you take out what you don't like it the game no longer seems totally overwhelming with features.
For example,
Uncharted = Press X to climb walls 90% of the game.
Witcher 3 = spend 90% of the game talking to tons of intricately modeled quest characters you have no idea who or what they are doing in the game since nothing makes sense.
This is absolutely not true. See the recent hugely successful release of Stardew Valley for just one example when you take a fairly popular genre (Harvest Moon-likes) that's completely unavailable on PC, and release a well-crafted modern game to serve that niche.
The mobile and PC games markets are flooded with shit and utter mediocrity. You do have to make something good to stand out, but that's far from impossible.
You don't have to look very far to find more under-served niches. What are some of the highest rated games on the 3DS or PS Vita? Fire Emblem, Persona 4. Anything like those titles available on PC? Nope!
Let's take game development as one example. You can feel mediocre because you wrongfully compare your progress and success against outliers like Minecraft. However I don't think most people who want to be good at game development are ignorant of what an outlier is. It doesn't take much to learn how big the climb is once you start.
The real difficulty is that the tools have been democratized. The market is flooded with games from developers of all skill levels. Even the most niche games have so many options that most games have trouble distinguishing themselves from the competition. It can be disheartening to realize that your most unique and amazing idea is not unique or novel in most respects and that it will be competing in a pool of several thousand games with similar ideas.
The other difficult factor is that the greatest games make the appearance of being simple and effortless. We only see the end result... not the 200 games the developer made before releasing the one we noticed. The myth that genius is a gift you are born with can certainly make most of us feel mediocre.
That's even before we get to fear of failure, social pressure, and market pressure! Many people want to be good game developers but they also want to feed their family and give their kids a good education... so they only have so much time in their lives to dedicate to improving and developing. Even if they are full-time game developers many of the same fears apply.
It's the tyranny of being just smart enough to know how much you don't know. It can also be a comfort though if you're not worried about being the stand-out genius and just like doing good work.