Your position would make sense if besides forcing the implementation of Apple Id, Apple forbade the use of any other authentication method. This is not the cas

Your position would make sense if besides forcing the implementation of Apple Id, Apple forbade the use of any other authentication method. This is not the case. You can even offer google authentication in your app. You can also move to android and authenticate to the same app still using apple id, the developer can also offer the chance to link this existing account with another credential. So, there's absolutely no lock-in. And indeed most apple users are happy with that, as it gave me the choice not to have to keep using google or facebook authentication.