I always chose to never use my real name on any social media accounts, if it was required I'd probably elect to not sign up, but their EULAs frequently are revised to serve whatever purpose they want because there is no meaningful regulation in place to limit their data mining practices on pretty much anyone because others post info about you in some way over time, even if you don't have an account.
Sometimes it's a legal obligation (under KYC), sometimes it's pressure from credit card companies, and sometimes it's just websites making shit up to enforce their own rules.
Twitter requires ID and personal information (i.e. your phone number) for verification even from users that are not involved in any sort of purchasing or income scenarios.
Reddit started out not caring about who anyone was, but over time IP based tracking and other things started to creep in...
Private companies that aren't regulated nor involved in conducting regulated business should not be asking for any government issued ID nor personal user data if you ask me.
Edit: I thought of two more: airlines and banks. But I assume both of those industries are required to by regulation.