The natural progression is from a little tyranny, like censorship, to full-on tyranny. Give in to the former your asking for the latter. From Brandon Smith at alt-market.com:
As I have noted in the past, in order to be a conservative one has to stick to certain principles. For example, you have to stand against big government and state intrusions into individual lives, you have to support our constitutional framework and defend civil liberties, and you also have to uphold the rights of private property. Websites are indeed private property, as much as a person’s home is private property. There is no such thing as free speech rights in another person’s home, and there is no such thing as free speech rights on a website.
That said, there are some exceptions. When a corporation or a collective of corporations holds a monopoly over a certain form of communication, then legal questions come into play when they try to censor the viewpoints of an entire group of people. Corporations exist due to government sponsored charters; they are creations of government and enjoy certain legal protections through government, such as limited liability and corporate personhood. Corporations are a product of socialism, not free market capitalism; and when they become monopolies, they are subject to regulation and possible demarcation.
Many corporations have also received extensive government bailouts (taxpayer money) and corporate welfare. Google and Facebook, for example rake in billions in state and federal subsidies over the course of a few years. Google doesn’t even pay for the massive bandwidth it uses. So, it is not outlandish to suggest that if a company receives the full protection of government from the legal realm to the financial realm then they fall under the category of a public service. If they are allowed to continue to monopolize communication while also being coddled by the government as “too big to fail”, then they become a public menace instead.