I think you’re missing the point of what most of the replies here are saying. Its not ‘just’ going off and playing games. Thats like saying “why don’t you just go and be an A list movie star.”
That said there are thousands and thousands of people who are doing exactly that. I follow a few really good Twitch streamers who make a living off of playing games. You should find a nice community and give it a go. I highly recommend Cohh Carnage ( https://www.youtube.com/user/CohhCarnage ) for an awesome and fun experience. His playthrough of Pillars Of Eternity is one of my favorites.
Personally I would hate to be a YouTube or social media celebrity. I think that those communities are incredibly toxic and actually hope that one day smaller more focused communities (like CGTalk used to be) become popular again. But honestly, with the amounts of money that pour in from social media I doubt that will happen.