It's not a monopoly, it's a baseline. Like the postal service or Medicaid. You're always free to choose the non-government option if it suits you better, but the government option guarantees that there is something reasonable on offer for the 10% of people that corporations deem "unprofitable". Old people, sick people, poor people, rural people. It doesn't have to be great, it just has to provide this now-essential service for those who would otherwise fall through the cracks.
> it's a baseline. Like the postal service or Medicaid
I think the interstate highway system might be an even better example. An absolutely essential part of business infrastructure and personal lifestyles, built and maintained largely at government expense, yet hardly anyone is asking for it to be torn down or privatized. Not even the parts that have tolls. (Yes, there are a few who suggest this, but even by right-wing/libertarian standards they're considered a bit crazy.) Just as anyone with a driver's license can drive on an interstate, anyone should be able to participate in the internet. It's not that much of a stretch from there to saying they should be able to participate fully, which means being able to host sites or apps. It doesn't have be be completely free of cost (see: tolls) but should be freely available and run for the public good. That's no crazier than the interstates.
The danger of course is that this turns in to a subsidy for the private interests. If they can avoid serving the unprofitable because the government will pick up the slack, then tax payers are paying for the service of that 10% and private business gets all the profit from the rest.
Either you need industry charges to cover that cost to government, or a mandate that they can't ignore expensive customers.
Maybe, but more targeted than that. You could tax health insurance companies to pay for a public system, or you could put a surcharge on phone bills paid directly by the consumer to subsidise service to rural users.
There are lots of options each with their own trade offs.
Even if it's a monopoly (not strictly required), nationalisation means the nation becomes the only shareholder, and the profits are directed to the growth of the nation rather than the business.
Apps are probably not the right target for that, but Amazon might well be — it has expanded to the point it needs its own delivery network because government owned post isn't enough in certain countries.
It would be a massive pain to do this well, certainly more than would fit into a comment box like this. And not just because it's a multinational, and different governments will have different opinions about the process of nationalisation.
Because they'd operate at cost, which is wildly out of alignment with what the market will charge you for a CPU cycle.
I'd bet that <10% of what you pay for an EC2 instance is hardware acquisition and labor and electricity. The other 90 is in support of the never ending zero-sum game that is fighting over market share.
Compare it to municipal internet, in which you usually pay less to get more because you can fire the marketing department.