Social
The framework allows connecting any social network like Google, Facebook, Twitter, and even GitHub as an authorization provider. Each of them is good on its own, handling identity validation and password recovery flow outside the framework.
However, if you want more than one social provider you have to use the System provider to unify them. It also makes sense to use Metamask provider to attach the wallet to the account. This is already at least 4-5 providers that all together could be replaced with Firebase provider for simplicity.