I had the same thoughts as much as 2 years ago on how this will play out. Unlike with railroads and fiber optic cable however, the core infrastructural asset of GPUs tends to become rapidly obsolete after about 5 years. Commoditization of this scale of compute is definitely going to be a boon for many fields of research. Unfortunately fundamental public research is exactly what is being cut right now in the US. Long…
Is it all about the actual GPUs though, is that the only "infrastructure" being built? A list from the top of my head of things that I'd say do last:
1. Data center buildings (take a while to build, contents completely aside).
2. Organisations and processes for running operations and procurement in said data centers - doesn't take decades to build for sure, but it's something worthwhile to already have.
3. Advances in the actual chips, i.e. more powerful processing units.
4. Advances in chip fabrication.
5. Chip fabrication facilities and organisations (similar to #1 and #2).
So sure, GPUs are highly temporary. But a lot of the things being developed and built around them much less so.
I do think one possible bubble burst scenario is that we'll have cheap compute available for decades but not a lot of great ideas of what to do with it. That is not unlike the 2000s I suppose.