> There's no reason for their signup process to need anything more than a username and a password. They don't need my email address.
They do (and any service basically). You don't want to run a large-scale service without having some way for your users to self-reset their passwords.
> They surely don't need my phone number or any other information about me.
That requirement is recent and I believe comes from law enforcement / politicians as they want to be able to track "hate speech" (that's the official speech, but rather I believe it's about dissidents, YPG supporters etc) to real persons. Many left-wing German accounts had them frozen until entering a phone number, for example. Facebook is easier because many people use their real name and photographs or other personal details from which law enforcement can identify them.
They do (and any service basically). You don't want to run a large-scale service without having some way for your users to self-reset their passwords.
> They surely don't need my phone number or any other information about me.
That requirement is recent and I believe comes from law enforcement / politicians as they want to be able to track "hate speech" (that's the official speech, but rather I believe it's about dissidents, YPG supporters etc) to real persons. Many left-wing German accounts had them frozen until entering a phone number, for example. Facebook is easier because many people use their real name and photographs or other personal details from which law enforcement can identify them.