Here are a couple argument why it shouldn’t be legal:
Patreon: In the real world, you can’t just give money to a business for nothing, there has to be some kind of value exchange. Patreon probably has some bullshit in their TOS that you’re not actually donating, but buying some “perks”, but that’s not what a lot of youtuber’s convey in their messages. To accept donations the “right” way, they would have to register a non-profit entity, then they’d have to publicly report exactly how much they received and spent, from where and on what. If they also do ads they’d have to also have a separate for-profit entity, and overall they’d have to be very careful with how they use the money as the non-profits can’t just give money away either. None of the youtubers I’ve seen actually do this.
Ad integrations: It should definitely be against Youtube’s TOS to have ads inside the video (and possible other sponsored deals), because most major channels can easily find their own funding, disable google’s ads and use their infrastructure without paying squat. And if they don’t, by doing advertisement themselves they’re still Google’s competitors, as you can’t shove infinite amount of ads in a video - the viewer’s patience is limited and they tend to either leave the platform or set up ad-blockers, both of which cut into Google’s revenue. So what I meant by “charging creators” initially, was some kind of deal among the lines of “If your video reaches 100.000 views, you owe us $0.10 per 1000 views over that, unless your video has ads enabled and not demonetized” or something like that.