It's also incredibly capital intensive to deploy and maintain. Land, construction, property taxes, energy cost, network costs, not to mention servers and GPUs (or whatever is next for Ai, ASiCs?) that will need to be upgraded frequently to remain competitive...

The engineering of all this, hardware and software.

The government doesn't generate revenue, except through taxes. They would have to seize the means of production, hyperinflate the currency, insane tariffs/taxes, or my best guess, some combination thereof.