Here is something that bugs me with “Sign in with Apple” or with services that are supporting this feature.

The easy and fun part is when you sign up as a new user of a service supporting “Sign in with Apple”. But what if I’m an already signed up user for many years then I want to switch to “Sign in with Apple” without creating a new account? Some service are providing a way to link an Apple ID in order to enable “Sign in with Apple”. But it is the minority. is such an example.

Am I missing something?