Should Social Media companies protect the identities of their users?

Regarding this civil case for Twitter to reveal the identity of an account, is it similar to how a journalist protects the identity of their source? Or is it different when a person communicates to the public directly without editorial input or review? Is it relevant that the ‘communication’ was proven to be false? Or is it free speech?

Do you think it will quiet other anonymous social media accounts that spread disinformation if they can simply be sued to find out their identity? Or will it open up the door to online harassers threatening ‘legal’ doxxing?

This is not a criminal case, it’s a defamation suit. So, I’d like to not address protecting identities of someone under criminal indictment because I can’t imagine that’s too controversial. I’m sure we all expect them to give it up if a crime has been committed.