It sucks that often our only option for this kind of authentication is Facebook or Google, since they only see this as a way to harvest even more data about the

It sucks that often our only option for this kind of authentication is Facebook or Google, since they only see this as a way to harvest even more data about their users. Apple's implementation is a lot better on this front, but you're still placing your trust in a trillion dollar company. And lots of sites choose not to implement it because Apple's design makes it harder to track users across domains.