I’m talking about the most common happy path that they don’t want to optimize - the user registration/login

I hate typing a secure password on a phone and I want to evade this process whenever possible. Using Sign in with Apple you don’t have to type a thing and you confirm using FaceId.

It seems like the problems they were facing require different UX solutions than they already had or some bug reports to Apple (if the feature is really missing something).

For me it is much better to use Sign in with Apple as the user as the flow is simple, unified and Apple has a track record of caring about privacy, where it is often not the case for randomservice.io