"would encourage more infrastructure to be produced with that revenue"
Wrong. They will be able to earn more money with less investments in infrastructures. As soon as the network saturates, increase the prices for prioritization instead of improving the network. It's cheaper, and as customers has no options, they will be forced to pay.
Actually, that already happened in the past when there were actual monopolies - for a long time telco preferred to keep call prices high - especially the long distance ones, but in many countries they billed by the minute/second even local ones to avoid people kept lines in use for a longer time - to cut down on the needed investment to increase the number of calls. Some people were even connected with lines that allowed only one customer call at a time among two or more, again, to save on infrastructure.
When you're able to set the prices, you will try to squeeze as much as you can from the actual infrastructure instead of spending for an improved one.
Another example? In Italy the ex-incumbent and owner of the copper network is complaining that the new company which is deploying fibre is not letting it to get enough return of investment on its (quite limited) VDSL deploy on cables that for a lot of houses are over forty-fifty years old (and were already paid many times over), and is trying to put its hands on the other company to delay fibre deployment, as its plan was to spend little to deploy some cheaper VDSL to meet the new minimum broadband requirements, and avoid to deploy the far more expensive FTTH - and keep on screwing the customers with lower quality connection (good luck to get decent VDSL speeds on longer and older cables).
Capitalism "work" - but now always in the right way - especially when the power of the involved sides are really imbalanced. It could work just to extract more money from the base and accumulate them at the top, giving shitty services in exchange. It happened, it happens, and will happen - as long as there aren't rules to make the system more balanced.
"The store with the high prices" does it slow down stores with lower prices? No, it doesn't - straw man argument.
Would you like a power/water/gas system with consumer prioritization, where people with more money than you can in some situation cut those supplies to you? Maybe because they have to fill a swimming pool and who cares if you can't have a shower maybe after an hard work day? Or have a party and who cares if you can't have enough power and water to make your laundry and cook your meal?
Class envy looks now to be the domain of those who believe that having some more money gave them more rights, as they think they're really a separate class which special rights. Just like before French Revolution, and rolling heads.
Allow that - which is truly anti-democratic - and you'll push people toward Marxism, which was the wrong answer to real existing big inequalities.