It's also profitable.
If you have to scan drivers licenses to access Facebook, storing and verifying that information can be outsourced to a company which oh wow what a coincidence is run by a Facebook subsidiary. Technically regulating the internet, AND you are made richer!
Godspeed You! Woke Moralists
Mandatory age verification and the banning modern public towns squares for young people is, and forever will be, governmental and societal abdication of responsibility so that those in charge don't actually have to dare hold big tech accountable for the very real public harm they can foster.