My concern with this is how far it goes and whether it has unintended side-effects.

There are a lot of situations in history where in retrospect being able to evade government oversight and restrictions turned out to be a good thing. During the Holocaust a number of Jews and other targeted populations were able to escape hostile territory because they were able to get forged passports and other documents, something that strong cryptography would make impossible (even in a perfectly privacy-preserving way).

I'm not sure how old you are or when you started in tech, but in my case I started as a kid and was able to build the skills that now gave me my career thanks to unrestricted Internet access (and sure, I saw pornography a few years earlier than I should have - didn't seem to have any measurable detrimental effect on me, especially not compared to the cigarettes and alcohol).

This wouldn't have been possible if age verification was properly implemented, since a lot of the resources that might be useful for someone to learn programming/sysadmin could also be used to circumvent age verification and thus would've been blocked, and I would probably be working a minimum wage job and/or engaging in crime to sustain myself as a result. If I had to choose whatever harmful effects from pornography versus having a min-wage job, I'll take the porn side-effects any day, at least I have a roof over my head.