Making a comparison to renting a space is an apt analogy, but doesn't go far enough. These social media platforms function as a modern public square. A public place owned and operated by corporations.

In the civic center where I live (San Francisco) people can protest, gather, bicyclists can shut down traffic, homeless people can camp out and live, illegal drug dealing is out in the open for all to see. In other words it is a free for all, and as long as major crimes are not committed then all is tolerated. This is freedom to gather and associate.

People pushing for corporations to police these digital public squares are corporatists who want corporations to have power over all society. It is not freedom of speech, but rather freedom to gather in the digital public square.