You're right and I'd go a bit further: It's none of their business what your age even is, they need to know only one bit for their legal duties, over or under age of majority.
Basically what is really needed is a certificate of majority digitally signed by the government bound to some identifier, email address or full name. All this uploading faces or ID card scans is ridiculous.
You just reminded me: A while back there was this slew of articles coming out of the tech press saying MP3 was now dead.
And why did they say that? Because the last Fraunhofer Patent on an MP3 related invention ran out.
Instead of reporting the format was now fully free, those idiots thought that meant it was now dead 😂