My son discovered YouTube gaming channels and I'm losing my mind

So my 7yo watched maybe 30 mins of some guy playing Minecraft and now that's ALL he wants to do. He's asking me every five seconds if he can watch more videos. I set a timer for 1 hour on weekends but he's started sneaking into my office to use the tablet when I'm not looking.

The worst part? Some of these channels have weird sponsors and I don't even know what half the stuff is. How do people actually monitor this? Do I need to go through every single video he watches?