There is a market of sorts. If there is no fast internet in some village, the a private company has to evalute the cost benefits. They can achive a local monopoly but they can not make prices to high. Peole have lived there befor there was high speed internet and if your price is too high, they have not lost anything but yoi lost your investment.

So the telco has to evalute, what the investment cost and how many subscriptions they can sell. If they set it to high, not enought people will buy it. So the market is esentially against how high people value your product.

Also how is the cost cost covered by the state? It is not generally true that the internet is better with more people, specially people who dont value internet highly.

Also your argument can be made for anything, for example, if everybody loved product X then marginal cost of production goes down and that is bettwr for everybody. So would you want the state to enlarge the market for product X, just because it would be better for everybody?

Also its a question of cost, for example, i prefer if there are more people in the internet, however if you ask me how much im willing to pay for otber people getting internet then my answer is pretty much 0.

You are completly ignoring the cost aspect of the cost benefit calculation.