How is it KYC?
I did not know about Hawthorne effect, I was simply calling it the panopticon, thank you.
Discussion
It's KYC because the adults are the only ones who actually have an ID to submit. So while children may indeed not be able to use the service, every single adult who does has now been forced to give their full identity. This can be saved along with other data to for use by government, commercial actors, or data theives. I use KYC in the loose sense. It isn't technically, but it has the exact same outcome.
There are some exception in the US where a 16 year old + may have an ID, but that's an edge case.
The only freedom oriented approach is to allow parents to parent their children rather than have the government do it for everyone.