A few of the successful (mostly) Sherman Act court cases the government has undertaken (not all): Standard Oil, American Tobacco, AT&T, Northern Securities (Railroad), Swift&Co price fixing (meat packing), Kodak, Paramount Pictures.
I could see and understand Verizon, AT&T, etc made were in collusion to make internet access more difficult for republicans versus others. That would seem to fit under Sherman Act regulations and sort of matches up with Swift & Co, Kodak and Paramount Pictures cases.
I could see if Facebook kept individuals, based on politics or something else, from posting on other sites due to collusion, that also would seem to fall under the Sherman Act.
I just am not sure I see that an independent company can be made to "fair" and that is in quotes because each of us defines "fair" differently. Facts are facts, but fairness is in the eye of the beholder.
What if Facebook said, from now on anyone who says their a Republican can't post. Uproar! Unbelievable! the death of their financial future! But, legal, stupid - but legal.
What's to stop FoxNews or Newsmax from opening a FB rival that caters to conservatives? Free and open posting of all ideas! Users may flock to it, money to be made. Completely legal.
IMO