Update to the above, since it's too late to edit: It looks like Apple is in fact forcing you to support this sign in method, if you also support Google/FB/etc.:

Update to the above, since it's too late to edit: It looks like Apple is in fact forcing you to support this sign in method, if you also support Google/FB/etc.: https://9to5mac.com/2019/06/03/sign-in-with-apple-requirement/ https://9to5mac.com/2019/06/03/sign-in-with-apple-requiremen...