What 2000 page auth(n) are you referring to? authn may use aspects of cryptography but it’s largely orthogonal. The point is, it’s fine to roll your own authn.
If you don’t want to roll your own authn, you’re delegating to oauth (oidc) identity providers like google/apple/facebook/etc., which not everyone has an account.
If you don’t want to roll your own authn, you’re delegating to oauth (oidc) identity providers like google/apple/facebook/etc., which not everyone has an account.