National labs sign "cost-effective" deals. NVIDIA isn't cost-effective. Aurora (at Argonne) is all Intel GPU. Aurora is also a clusterfuck so that just tells you these decisions aren't made by the most competent people.
They are competent people, just not in the fields techies want.
When you're a national laboratory and your wallet is taxes from fellow Americans, it is very important that you find a balance between bang and buck. Lest you get your budget slashed or worse.
nvidia absolutely gives deals to national labs and universities. See Crossroads @ LANL, Isambard in the UK, Perlmutter @ LBL. While AMD is being deployed at LLNL and ORNL, Nvidia isn’t done with their HPC game. Maybe not at the leadership level, but we’ll see how Oak Ridge and LANL decide their next round of procurements
"Winning" a national lab definitely confers benefits far beyond just financial ones – these are, by definition, the biggest deployments in the world. Both the technical experience setting these up, and the reputational benefit associated with this, is worth a great, great deal. (I don't know how much money HPE Cray makes, for example, but I'm sure it's not the money it makes that's stopped HPE from quietly sunsetting the brand.)
