The % cut of $revenue is outside the main scope of my comment, which concerned child labor, a somewhat independent issue. It doesn't matter too much to me the % monthly revenue a 12 year old kid gets, I'm more concerned with the promise of unlikely riches encouraging kids to work long hours outside the oversight of traditional child labor laws. If that 12 year old is putting in a 30 hour work weeks then I think it's problematic regardless of the revenue with some minimal enforceable guardrails. I don't think parental signoff is sufficient either: the entertainment industry has plenty of examples of how that can go wrong, and also how some of those minimum guardrails might work.

Do those other places host creators' applications for free regardless of scale, and without injecting ads into your entertainment?

Youtube doesn't have their own currency simply because they don't have to, not because they are kind. Their major source of income is ads and subscription. Neither of these needs their own currency. Highly unsure what your point is.

I'm not sure either. Particularly how, even in the presence of any policies, they could police the system: Does YouTube send someone around to check on the Ryan's World kid and the work environment?

Even with child labor policies it doesn't seem like platforms would be much better at managing them than content moderation.