I mean yes, the verification service would know about you. But since this is a trusted service, it would be me okay. It doesn't even have to store the verification result, if you don't want to
In my opinion we would need an EU service that does the verification while sharing as little information as possible with facebooks services.
I think the EU service should only send back, if the person is allowed to use Facebook. A single yes or no. Which could mean both, that the person is either old enough or has their parents consent.
This is, why Lemmy will probably never be successful.
People are told to choose any instance and they choose the biggest ones, because that's also probably the one with the most content and activity. And after that other people will tell them they made a bad choice and it's their own fault.
Some years ago it was even possible on Android to send any link from any app via the sharing menu directly to the desktop. It was very infuriating when Firefox removed that
Yes, I think that's the best way.
This way you are not restricted to people who have Instagram, you can just go into others homes and tape your art on their fridge.