So many people these days instead of creating separate account to some websites (login/password) the use instead integrated Login via Facebook button. I tried to educate friends and family not to use this feature even for the reason that if their FB account will be blocked they will loose access to many other websites. However many people give up because it's not so convenient as to just clicking one FB button.

I have accounts with a couple of banks and can't say I've ever seen them using OAuth. But if they did, I'd consider other banking options.

how is using OAuth any different from using your email for a password reset.

I would not want to rely on a social media company to vouch for my identity for something as crucial as my finances

I agree that single sign on takes advantage of people not understanding what they give up when they choose FB/Google for SSO. What government policy could fix that? The fallback seems to be that people just re-use their email address in all their accounts.

which probably brings them back to a google or microsoft email account. back in the early twenty teens facebook even tried running a email service but killed it latter. if this were to happen it would probably make a comeback.