The big joke is that they really are not “private business”.
1. They are publicly-traded corporations, not private companies.
2. IPO = Initial PUBLIC Offering.
3. Operating in the Private Sector does not equal operating as a Private Company.
4. These are already regulated by the SEC, FTC, and CDA Section 230.
5. Under that last they are legally required to operate as open platforms, without any publishing/editorializing of content, in exchange for Federal protection from liability for said content.
6. If Congress did its job, there would be no need to invoke anti-trust regulations.