I don't consider myself a libertarian by any stretch, but isn't their argument in favor of a completely free market? If so, any government regulations that protect these de facto monopolies would not be supported either, as they are by definition creating a regulated market.
Wired broadband companies can't exist without government support, because they need right of way to run wires across many peoples' property. The problem is that governments tend to give permission to do that to only one or two companies.
Which is what libertarians hate. The argument against government is that government unscrupulously uses eminent domain to seize land at below-market prices, which is then handed over to the ISP. Government's intervention a la eminent domain takings favors the most-favored-ISP. So what they're doing now in NC is have government step in to solve government problems, which doesn't solve the cause of the problem.
What land in NC has been siezed by the givernment and handed to an ISP?
Look, just like phone, water and electricity, broadband is a natural monopoly, at least until peer-to-peer access becomes a reality. Not many people complain about the city running water servives because often it is just more effecient. Broadband is no different. The only" scary" thing is that thecity might screw it up. And while that is a possibility, at least you as a citizen can directly participate in how the tech is rolled out and indirectly participate by voting. OTOH, good luck convincing your cable provider that last mile fiber is a good idea.
Many libertarians hope to convince the government to reduce regulation and protection of BigCos, instead of adding more regulation to make the market "fairer" for other players. But I got to agree that's not very realistic with all the lobbying going on.