alt Hacker NewsThen you recognize that the solution definitely does not require privacy invasion, since presumably Facebook does not want actual proof because they hope teenagers will get around it.
That being said, the antiregulatory wonks are not all working for Facebook, and some are indeed manifestly just always opposed to any regulation at all no matter what harm is occurring.
Bear in mind the alternative: Things like Discord collecting personal data to do verification at the website level. A push for a simple "user is over 18" header is incredibly preferable from a privacy standpoint and parents being able to control and monitor it themselves.
This legislation does not require it out of the gate, but it sets up the precedent and the incentives such that it will eventually be required down the line. That's the problem with anything that gives more power, and the expectation of even more power, to the server (ie to big tech).
FWIW I personally would be supportive of legislation where the data flow went the proper way of server->client, for the user-agent to decide. Consider: Any website over a certain size must publish an appropriate set of well known tags asserting whether its content is suitable for kids of certain ages, has social aspects, the type of content, etc. Any device preloaded with an operating system over a certain marketshare must include parental control software that uses tags, as an option in the set up flow. The parental control software "fails closed" and doesn't display websites without tags. The long tails of the open web, bespoke devices, new OSes, etc remain completely unaffected.