I think in most cases supercomputers are in fact "flexible arrays of less powerful nodes". It's just that you need to change the architecture as you scale up the number nodes and type of nodes. Basically, you need fast data transfer and memory sharing between these nodes if you want to do anything but the most embarrassingly parallel problems.
Not all engineers live in SF and make more money than they know what to do with. What are the kind of services that most engineers and coders are paying through the nose? Attorneys, financial services, therapists, etc.
Why not have more schools training these professions?
One problem with inflation is that wealthy people and corporations own a lot more assets like real estate, factories, patents, brand names, mining rights etc. while common people put their savings in fiat-denominated bank accounts and sometimes questionable debt instruments through their pension funds. So inflation is going to take a toll on a lot of middle class savings and old age survival funds for regular people.