Why does the USA still love Prog?

[PFD]

I'm not so sure I agree with your main premise. I think classic prog bands still gather a crowd in Britain. Yes still tours there, as does Jethro Tull, (when Ian's not fish farming).

I know of bands, on the other hand, that can perform to far more people in Britain than the USA. Marillion being the key example. Their last album charted 3 singles in the UK (albeit through a contrived promotional scheme), but didn't make a dent here.

Porcupine Tree, although gaining in popularity in American, have been performing for years in Britain.

Pendragon...IQ...Arena...all do reasonably well in the UK.

I think the main difference is population. If only 2 per cent of America's population likes prog...that will always be a larger number than 2 percent of Britain's population.