I actually read a book by a noted libertarian economist making the case for privatizing all roads (its easier to tear down a stupid argument if you start by taking it seriously).
What I expected was, y’know, just a bad argument. Like, there would be a bunch of super positive assumptions about how a bunch of stuff would work out that just don’t work in reality, that sort of thing.
What I got was quadruple decker raised glass highways with holes cut into them for rain to fall through.
No, you did not hallucinate that sentence.
That is the libertarian answer to how you solve the problems with privatizing all roads. Every road, even those in cities (especially cities) is actually four or five competing roads stacked on top of each other, owned by different companies, made of perfectly transparent glass so as not to deprive anyone living below them of their God given access to sunlight, and full of holes so as not to deprive anyone of their God given right to rain.
The author comes to this conclusion after realizing “Oh shit my libertarian homesteading fantasy doesn’t work if Jeff Bezos can just build a highway over your property, but my private roads fantasy doesn’t work if Jeff Bezos can just buy up a thin strip of land all the way around LA and then charge people a thousand dollars to cross it.”
This is the core problem. If you want a use tax for driving, attach it to vehicle ownership (Canada does this with plate stickers, for example). If you make it specific to which roads people drive you just end up with fast roads for some and slow roads for everyone else, and a whole lot of under-utilized infrastructure capacity.