Seems fair

there's not really a reason not to

There is though. If their IP changes then what? Some unlucky person gets an undeserved ban? If they're on a VPN then everyone sharing that VPN gets banned? It's a lot more hassle than it's worth. They're better off just taking the ML approach to prevent these types of comments being made in the first place and also taking action against videos that contain minors for their own protection possibly by automatically locking the comment section and if the uploader chooses to allow comments they can. Ultimately what it comes down to is how much would we allow them to infringe on our (metaphoric because technically Freedom of Speech does not extend to YouTube) rights.

/r/mildlyinfuriating Thread Parent Link -