Infrastructure isn't a free market. If it were, there would be a hundred different cable lines hanging outside your house, like what happened in the 1800's.

So, in order to prevent that situation, we allow one company a monopoly on the market. In exchange, that company is forced to follow common carrier rules, such as not interfering with speech.

An entrenched-monopoly dominating an industry primarily controlled by network effects isn't really a free market either, free markets don't exist outside of college econ textbooks.

We all agree to use the same company for infrastructure, just like we all agree to use the same couple of companies for social media. It's just when the social media companies do things that are bad people pop up and say "they are private companies in a free market they can do whatever they want" because these companies are new and cable companies are old.

I think the point here is that Twitter and Facebook increasingly look like a piece of infrastructure - it's hard to reach the general population without them, it's hard to opt out of using them, etc.

The reason Comcast is a monopoly is because if it wasn't, 21rst century networks would be like 19th century networks? Nice try, Comcast.