Okay so here's the thing, some games do better than others, but really, you can make money playing probably any game you can think of.
They're all profitable if you have the right angle and monetization channel(s).
Some obviously easy ones would be like World of Warcraft, Hearthstone, really any Blizzard game, League of Legends, and Call of Duty.
These games are already really popular with lots of people watching, and some have affiliate products out there you can promote.
People watch those a lot so, despite having to yell through the noise, you've got a lot of ways to monetize and you don't really need any sort of angle.
You're just playing a popular game.
If you're playing old games, or maybe some unpopular indie games, the best way to do that well is to find an angle.
That angle I keep talking about.
For example, maybe your thing is that you only play RPGs from before the year 2000.
Of course, those games won't have really specific affiliate products out there, but there will be other affiliate products you can sell out there that, with the right positioning, you can make a lot of money.
But that's only one example.
The Patreon/Podia route
actually works pretty well if you're working with games that aren't necessarily the most popular games out there.