My kid is only 3, but I am already contemplating time boxing and auditing gaming and YouTube time. It seems significantly more difficult than it ought to be, thanks to all the brain hijacking dark patterns out there.
Do so, no question about it! Once most children disappear down a YouTube rabbit hole of unboxing or gaming they're lost. It's scary to see how addictive our modern passive entertainment is. In my experience, the best thing to do is start limiting from early on. My kids are still under 10 and it's 1 to 1:15 hours of gaming + same of TV on each weekend day, never on a school day. They are hardly aware that YouTube exists, they only watch it with us.
This takes up a lot of our time, as we're their entertainment, but the times that I let go and let them watch more typically come back and bite me as they haven't had enough time to play & be creative and that leads to tantrums and bad bedtimes. We use Google Family to control their tablets and it's the timer on there that stops them playing, not us, which feels fairer to them.
Amazing. My kid just wants to get the build over with so he can get back to gaming or youtube, where he watches other people gaming.