It sounds like part of the problem was the national government selling the service instead of just leasing out the lines to private companies to use or better yet letting local government deal with it. A company might be willing to provide a better service than the taxpayers want the government to provide on their dime, but no private company could compete on price and it's a bad thing when the person who you depend on to fix the broken line to your customer belongs to your competitor because they can drag their feet and do shitty work. I've seen that first hand working in the CLEC space.
From a US perspective, private companies aren't any better about installing quality lines, especially the last mile, and won't bother servicing massive numbers of people at all because it's not profitable enough.
Cable companies in the US have been literally handed billions by the government to build out and improve their lines and the cable companies pocketed that money and didn't deliver anything (https://www.vice.com/en/article/study-throwing-taxpayer-mone...). There have been lawsuits and some investigations but mostly that money is just gone and to this day they still get handouts all the time with very little oversight.
We have the worst of both worlds. Corporations take tax payer money and also charge us for everything. The result is that in the US we pay more than the rest of the world does while getting far worse service. Handing the whole game to corporations and letting them dictate the terms (which included keeping out competitors until fiber, wireless, and satellite became options) has not worked out for us.
Basically the theory is that if you give control of infrastructure to the government they are motivated by keeping you happy because they work for you. You have direct control over them, can demand things from them, and in the worst case can vote them out if they aren't doing what you need from them. It's you (the people), choosing to spend your money (taxes), so that your own employees (government workers) can get you the things you want. Everything is transparent in both policy and accounting which means that you can see where every dollar is spent.
The alternative is to let corporation control the infrastructure and their one and only goal is to take as much money from you as they possibly can while delivering as little to you as possible (because that maximizes their profits). However much money it actually costs to deliver something to you, they will charge you 100% of that, plus more because they need to stuff their own pockets with cash in the process.
In fact they need to stuff more and more money into their pockets every quarter because any company that isn't increasing their profits is failing. Endless growth and "line go up" is all that matters to them. They will cut corners and increase prices every chance they get to make that happen. That kind of enshittification is bad enough when it's some company switching to cheap ingredients in your your favorite food, but it's unacceptable when it's a utility you depend on like internet access.
All of their accounting is hidden from you. You have zero control over how they run their operations. You have no power to vote out their CEO. You might have a choice between two or more companies (giving the illusion of voting with your wallet) but they all have the exact same motivation which is to take as much money from you as possible. This results in things like collusion and price fixing. It also causes them to subject their workers to low wages, little to no benefits, and outsourcing (to the extent allowed by law or even in excess of that if the occasional fines are cheaper).
In actual practice you get corporations using their vast amounts of ill-gained money to bribe governments and install their people in regulatory bodies making both options worse. The government option suffers because now they're incentivized to please corporations instead of the public and the company options get worse because companies can pass laws/regulations which further increase their profits at your expense. Either way, it's the companies who are the problem. We'll, the politicians taking bribes sure aren't helping, but companies are expected to exploit everything that they possibly can to increase the amount of money they make.
We still haven't figured out a good way to keep the government from taking bribes, but given the option, I'd choose the option that puts more power in the hands of the voters (and I say that even knowing the sorry state of our voters) because we at least have the option to turn things around. We have a lot of things to overcome (the deliberate dumbing down of the voter, the deliberate misleading of the voter, the efforts to suppress voters, the lack of accountability for government, the lack of consumer protections, the influence of money on politics, etc.), but it's either we try to have a say in how things are run or we bend over and accept whatever we're offered by companies who are explicit about wanting to take as much from us as they possibly can.
I think we'd agree that local government is much better than national. Ideally you'd have national regulations that make sure that everyone in the nation has a minimum standard of service, but leave it up to the locals to manage that and handle the details. We have more direct control over local politicians than national ones. They're more likely to live among us too which helps.