Really the regulation should be about requiring social media companies to interoperate similar to regulation on the phone companies. You should be able to switch to another social media platform without losing your ability to communicate with your friends on the old platform similar to how you can still call your friends after you change phone companies.
Then is if the social media companies want to charge money people could change to another platform without losing their contacts.
Basically the only reason I still have facebook is to talk to chat with people on there that I can't contact through other means.