Turn it into a utility. Having an Internet connection is arguably more important than a phone line ever was and is up there with electricity.
It’s a utility. Treat it like one.
I only have one option for most utilities. I don’t get to choose which private power company I use and I certainly don’t get to choose from an array of options for how that electricity is generated.
Making the internet a utility is good, but that won’t make it less of an oligopoly.
Here in NL they have a decent system if you ask me. Infrastructure for power is owned by TenneT, a semi-government organisation. Then power is supplied by private companies, from whom you can choose any one you want (aka the cheapest/greenest one, depending on your wishes). They then supply power to the national grid, so you’re technically using power from all companies, but paying your share to the one you have a contract with.