the answer here of course is very simple, you teach your kid what she is or isn't allowed to do "online" just like you do IRL. and you verify by either sharing the account so you can see what is being installed and/or checking the device...
parenting ain't that complicated...
Is this method of parenting that you are advocating for working out okay for you or do you not have children?
Myself, I am childless and I do not like KOSA as I am unwilling to give up the anonymous internet to keep the kids safe. At the same time I do think there is room for some regulation here.
The problem - especially in USA is that whoever is in power when the "regulation" is added - whatever that regulation is - will be 100% political thing. And say 50% of people will not be happy about it. The power shifts, we either scrape or put other "regulations" in place to make the other 50% of people happy - ad infinitum... I am against regulations mostly because they are never about "protecting kids" or whatever the "spirit" should be - they are always political in nature (e.g. your kids should NOT read these books nonsense...)