Follow your passion. It's going to get really old at some point getting up every morning, going to a job that does not excite you and does not make you happy, while at the same time second guessing yourself and secretly wishing you were making PC games. If your purpose is to make PC games and you are not fulfilling it, there will be this cognitive dissonance, or misalignment with what you are truly supposed to be doing, in you and it will keep gnawing at you and making you feel unfulfilled.

Secondly, don't follow trends. Trends don't matter and they change all the time. Mobile gaming may be the trendy thing today and tomorrow it might be something else. Just follow your passion and forget the trends.

The caveat to all this, of course, is that you have pay the bills and put food on the table. If you can make money following your passion, go for it. If not, get a day job doing whatever pays the bills and follow your passion nights and weekends. 

10 hours ago, SIr Pep said:

I like what @itachii said about Notch. With Stardew Valley it was the same thing. He took the faults he found as a consumer in games like Harvest moon and Rune Factory and simply made his game the "perfect" blend of both.
In my own searches for what your asking, one answer I got actually really hit home. "Make a game You want to make".

 

This resonates with me as well and it's also almost verbatim something Hideo Kojima said in an interview a few year ago. He was asked something to the effect of "What was your thinking when you were making the original Metal Gear?" and sis answer was, "I was just making the game I wanted to play." This has been one of the tenets of my game design philosophy, if you will, for years now.