[throwawaymaths]

that's a pretty funny example you gave, because the discovery of the chemiosmotic effect was not funded by the government, it was privately funded by a guy who raised money and holed himself up in a regency estate with an assistant for a few years to prove it.

https://en.wikipedia.org/wiki/Peter_D._Mitchell

[whatshisface]

Private and public philanthropy both contribute to science in the same way. If you're asking why private philanthropists can't replace federal funding, it's the same as the reason why we can't just make billionaires pay all the tax: the NSF budget would bankrupt Bill Gates in 13 years.

More realistically, what would happen would be that rather than sacrificing themselves for the greater good in some kind of voluntarily socialist outpouring of wealth, they'd ask us to look to China for our scientific future.

[throwawaymaths]

Stop doing expensive science? Some things can just wait for tech to catch up and make science easier by lowering costs.

An example is the superconducting supercollider. Chemistry and pharma industry were making NMRs cheaper and the cost of the supercollider components went down. So the LHC was a much more effective "buy" than the SSC.