Well, Sign In with Apple is different because:

1. It’s fast

2. It gives you a pseudonym

3. It doesn’t leak all your other social graph data

4. Doesn’t require a new password

The rest are:

1. Faster than creating an email, but will require redirects, and possibly logging into fb/google

2. May give you a pseudonym but often reveals your real name

3. Are used typically to build profiles of you and create stats on app popularity across demographics

4. Don’t require a new password.

Maybe it's just me, but one bummer about this kind of system is that's is A+ top security for a lot of stuff I don't care about. To create some account on a random forum to give feedback about how I got a stuck oil filter off of my '03 Civic, for example. With email+password I can just use a low security password because I'm typing on a phone. With these all-in systems my device isn't recognized so I'll need to type in some code from 2FA and type my long, unique password.

I know they're very popular, but there's so much long-term unintended baggage with using these singe signon systems...even assuming Apple's doesn't have the nefarious parts most others have.

Even setting aside Sign In With Apple, why are you consuming mental space and energy with a reused password and whether they should be throwaways or not in 2020, when all mobile OSes and desktop browsers integrate seamlessly with password managers?

Over here, I just use Face ID and 1Password does the tedious filing-and-remembering part that computers are good at.

I use 1Password on both my phone and desktop for logging in. Saving a new password on the desktop is easy. For the phone it seems rather tedious. Especially when, even on the desktop, many sign up pages have me submit 2 or 3 times because the username is taken, password too complex, or I didn't give them my phone number. I find it way less mental space and energy to reuse a weak password.

Sign in with Apple has the advantage that the service on the other side of the auth window doesn't get to see you actual email address. They're provided instead with an anonymized email address from Apple that serves as a forwarding address for you.

It's also easy in general to revoke permissions with these SSO providers rather than dealing with whatever the service's account cancellation protocol is.

What’s cool about that anonymized email address is that even if it gets leaked, only the registered service can use it to communicate with you.[1]

[1] https://support.apple.com/en-au/HT210318

Does this just cement you too apple? I'm assuming if you lose your Apple address, you have lost all linked addresses?

In most sensible authentication flows, your email address is not the primary key on your account, but rather just a credential with a link to an account, where an account HAS MANY credentials. You can usually "Sign in with X" and then "link" your now-existing account to credentials from "Sign in with Y" and "Sign in with Z."

That doesn't work if the email address the service knows as you, is a fake proxy at Apple.

It works as long as you add the second credential before losing access to the first.

Fair. Still a central point of failure, but not much (any?) worse than the alternatives.

Apple IDs can be arbitrary emails, and can be changed at any time (https://support.apple.com/en-us/HT202667).

I suppose it does. In the same way that using your gmail address to sign up for anything cements you to Google. But unless Apple or Google suddenly go out of business, I have a hard time seeing a problem with this.

Less than Google, really, because you can't change your main Google sign-in email at any time.

Login fatigue. Yes, I use a password manager (1password). But it means I need to stop going through the sign-up flow, jump over to the password manager, create a new login, change the password recipe from random-letter to random-word (which I prefer), generate a password, then go further modify it to accommodate the site's particular password complexity rules (upper/lower/special/numbers), add the URL, save, then go back to the sign-up flow to finish.

And... 90% of the time, that's what I do, because I prefer to have separate logins for every site.

But sometimes, I just click the 'sign in with google' because it's a hell of a lot faster and easier.

Hear hear. I’m amazed 1PW hasn’t defaulted to random word recipes by now, as well as providing checkboxes to fold in all the upper/number/special character rules, or min/max length. (My passwords usually look like this nowadays: “turtle megaphone house 6@B”)

Twitter does require your phone number to make the account sometimes. (I suppose if it can’t determine enough about you.) Recently I was able to make one, only to be locked out a few minutes later until I “confirmed my identity” by providing a phone number.

Do you signup with your self-hosted email?