Platforms, chokepoints and the law

[mnot]

https://www.hoover.org/sites/default/files/research/docs/who-do-you-sue-state-and-platform-hybrid-power-over-online-speech_0.pdf has some possibly relevant texts; e.g.,

Another important theme of the communications cases is the “scarcity rationale,” the principle that regulation, and the resulting burden on owners’ First Amendment rights, may be justified to ensure fair access to physically finite, exhaustible communications channels. The Court developed this doctrine in upholding fairness requirements for broadcast spectrum and later applied similar reasoning to cable. Some degree of government interference with the companies’ rights was justified, the Court said, to keep them from restricting, “through physical control of a critical pathway of communication, the free flow of information and ideas.”
Platforms like Twitter or YouTube do not exercise the kind of physical bottleneck control over communications that supported the Court’s rulings against cable companies. In this sense, user-facing platforms are also different from present-day internet access providers like ISPs, whose First Amendment challenge to net-neutrality rules was rejected by the US Court of Appeals, DC Circuit, in 2016.98 Speakers banned from a site like YouTube can still speak on Reddit or Twitter; users kicked off of those platforms may find a home on Gab or 4chan. They can also put content online using their own servers.
Many critics argue, though, that the platform ecosystem has created new forms of scarcity. Even if users can still speak on less-popular platforms, they argue, those may be inadequate because not enough other people are there to listen or respond.99 Following this argument, the economic success of a handful of platforms, and the resulting concentration of users— perhaps aided by network effects or natural monopoly dynamics—effectively creates new bottlenecks and scarcity of communications channels.

(p 18)