Where is the power grab? Everything is voluntary except for the requirement to support child mode.
Probably the government list. That part is a bad idea. It can be reactive instead, allow anyone to declare their site is child-safe and then punish false declarations.
The problem is that you cannot punish foreign websites, and there definitely will be ones allowing to bypass restrictions.
UK has no problem telling ISPs to block them or else.
Yeah sorry I meant to say in general this whole thing is a power grab like the acquisition on Tiktok.
I can't see any reason that passes the sniff test to say otherwise.