As I pointed out in my earlier post, I don't agree that fiber cables are anything like roads (or sewage, for that matter). "Infrastructure" means many things, and it's certainly not obvious that the same solution is the best for all.
My point was actually that when the inherently monopolistic aspect is factored out the free market can flourish. This is how it works in Europe.
I live in a Western European country. This is not how it works here. ISPs own their own cables. Yet I have four of them offering me service, four of them over fiber, but also cable, DSL and 4G. Yes, it's expensive. Many private investments are, yet they still get made. Yes, it's redundant. Reliability depends on it.
From what I've read, our situation is hardly atypical, as private installation seems to be the case in Germany, the Netherlands, Switzerland, Moldova, Slovakia and others.
The US case, on the other hand, it's hardly representative of a free market, and your problems can not be attribute to it.