I believe the core problem here is that ISPs and infrastructure are owned by the same companies. Based on evidence from other countries, like Japan, these problems would largely go away if it was illegal to own both the infrastructure and provide service to customers.That is certainly an idea worth exploring, but I'm not sure it's an automatic win.
We could consider European railway networks as a somewhat analogous situation. In several countries, one business or public entity owns and maintains the tracks and related infrastructure, while one or more others own and operate the trains themselves.
We have a better service here in the UK today with that model than we used to with the nationalised all-in British Rail, in some respects at least. On the other hand, the costs of that system are crazy, both in ticket prices and government subsidy, so it's far from clear whether the improvements have come because of the split in responsibilities or despite it.
We're not the only ones whose system doesn't always work, though. Every now and then, you see a real howler due to miscommunication, as IIRC the French had recently when it turned out that the super new trains wouldn't be able to fit next to the platforms at a load of older stations.
It seems to me that the main problem with ISPs in the US is not so much being both infrastructure provider and service provider as it is having little if any real competition on either count. Rather like the banking system, the US appears to be maybe a decade behind most of the developed world in this respect, for no particularly good reason. I can only assume it's a consequence of politics and/or questionable business environment.