You are already paying for several national lab HPC centers. These are used for government/university research - no idea if commercial interests can rent time on them. The big ones are running weather, astronomy simulations, nuclear explosions, biological sequencing, and so on.

The biggest run classified nuclear stockpile loads, at least in the US. They cost about half a billion apiece. And are 30 (carefully cooled and cabled) megawatts. https://en.wikipedia.org/wiki/El_Capitan_(supercomputer)

No chance they're going to take risks to share that hardware with anyone given what it does.

The scaled down version of El Capitan is used for non-classified workloads, some of which are proprietary, like drug simulation. It is called Tuolumne. Not long ago, it was nevertheless still a top ten supercomputer.

Like OP, I also don't see why a government supercomputer does it better than hyperscalers, coreweave, neoclouds, et al, who have put in a ton of capital as even compared to government. For loads where institutional continuity is extremely important, like weather -- and maybe one day, a public LLM model or three -- maybe. But we're not there yet, and there's so much competition in LLM infrastructure that it's quite likely some of these entrants will be bag holders, not a world of juicy margins at all...rather, playing chicken with negative gross margins.

>The big ones are running weather, astronomy simulations, nuclear explosions, biological sequencing, and so on.

these things constitute public goods that benefit the individual regardless of participation.

Many more people materially benefit from e.g. good weather forecasts than form video slop generation.