Anyone can make an account, though, and instantly access that content, so Elon doesn't really have any leg to stand on by claiming they're private. It's not the same as Cambridge Analytica scraping stuff you had to have certain privileges to see by tricking the system into granting those privileges.

Elon unfortunately may have a leg to stand on, because it doesn't functionally matter whether "anyone can make an account and see it". I don't believe any legal ruling to date has been fine with that distinction.