Where does your cutoff apply? At what point are there "too many users"? How would you prevent something like that from being a completely arbitrary platform killer?

The courts would decide just like they do when a company is thought to have become a monopoly. This is not a new problem entirely but in this hyper politicized moment in the country it somehow has turned, just like everything else, into a left vs right issue. Its pathetic how we lost the hability to look at the issues without partisan glasses.