Yes, you can do this with considerable effort.
But the moment you use OIDC with Apple ID there is a good chance you will lose many of the accounts created this way.
The issue is rather, that most people rely on these convenient services 100% and dont (want to) think about what happens in a bad case scenario.
I’d say email providers are an even bigger problem though. Good luck getting your accounts back if you lose access to your own email account. I don’t know that iCloud mail is particularly popular, but the risk really applies to any provider.