One person saying "no" can stop an entire city from getting new infrastructure.
Wrong. Ever heard of eminent domain?
Governments don't create cable monopolies.
They absolutely do just that when they subsidize the creation of the network infrastructure with our tax dollars, then allow a handful of huge conglomerates to profit off of that forced community investment while gouging the shit out of us and fight back any competition via litigation. Yeah, in the US, not only does the gov't create cable monopolies, it protects them.