I don’t think BankID has any sort of SDK that lets other apps access user data like that? All interaction with BankID I know of at least is triggered with the app needing authentication/signature opening a BankID session to the central service where you enter your authentication and then the BankID app is used as MFA to verify this.
Or am I misunderstanding what you are saying completely?
Most kids here in Norway get a bank account with debet card and BankID with it at 13. Implementing a solution to use it to verify if you are older than X years old would actually be less work than your proposed solution, both for the social media site, banks, the kids and the parents.
BankID is it’s own trusted platform. It is not connected to any of them. I am not sure if I understand what the other person is trying to say. Maybe they are afraid that Google and Apple can use BankID verified sessions to better identify the user?
Oh I see. Thanks for the clarification. Is that something they could have gone without and still be as secure as possible?