When certain platforms we now use every day for public discourse began, they attracted all classes of people on the basis of equal and fair access and non-discrimination.
(Pictured, Bill Collier, founder of The. Upadarian Society of America, at Google's Washington, DC headquarters. )
Having gained the audience and now being the major, even primary, effective means of public discourse, they are now CHANGING into platforms that discriminate against users of certain classes who have come to depend on these platforms to communicate to the world.
This is a bait and switch somewhat like a company that sells at a loss to drive out competition and then, having gained a monopoly, raises prices to the roof.
When in the course of events one class of people are denied freedom to speak freely, recourse is made to means other than talk. This can prove to be very dangerous for civil discourse and undermines the very basis of a free society in which discourse replaces force and violence.
It is therefore necessary that all public platforms, that is any platform that attracts users on the basis of a promise of inclusiveness, carefully avoid any acts which favor any class of people over others. It is in the interest of public order and civil society that no class of people is efffectively denied access to platforms which a significant portion of society utilizes for public discourse.
Whoever operates in this public space, even private firms, on the basis of being a platform for all, must not then use that platform to discriminate against any class of persons, save actual lawbreakers who use the platform to break the law.
Having gathered an audience, and profited thereby, on the basis of such a promise, it cannot be ethical (and should be illegal) to then use that platform in a manner that substantively effects discrimination against any class of people. This cuts certain classes of people off from the public discourse because a substantial portion of that discourse occurs on these platforms!
This is especially true when said platforms own a near monopoly over the communications and expression space, as a few privately owned but public-space platforms do today.
In an environment where nornal market forces could not efffectively provide competitive alternatives, one can argue that discrimination against people for using that platform to advance otherwise legal opinions or purposes, while favoring others, constitutes both a tort on the class of people discriminated against and an abuse of the public trust.
In short, for platforms which operate on the basis of serving the general public, discrimination against users of certain classes should be illegal.
If a platform serves only certain classes of people, its owners have a right of free association. Only platforms which have been built on the basis of being for everyone would be covered under such an anti-discrimination law.