You guys fell for memebait

Stores the user’s birth date for age verification, as required by recent laws in California (AB-1043), Colorado (SB26-051), Brazil (Lei 15.211/2025), etc.

https://github.com/systemd/systemd/pull/40954

And it can be used to verify how old you are.

How?

This is the part I’m hung up on. What actually physically happens to make me enter my real birthday in the systemd user field, and verify it’s actually my birthday?

January 1 1900 has been my official online birthday forever.

I guess the idea is that your parents store the date and you don’t get root access (or you store the date for your kids and don’t give them root access).
Then what? What stops the kids downloading and running whatever software they like?
Linux is build with different users in mind. So it is not a problem to forbid a user to run any program the root don’t like, or run only programs the root like.