The "layman" libertarian argument for austrian economics over keynesianism is that keynesianism will always result in a massive upwards transfer of wealth under a capitalist system at least in the short term (as you can always tax it back).

Under the gold standard you didn't really see countries hyper inflate, and the value of an average person's wealth wasn't in decline relative to that of the ruling classes. However there was massive economic stagnation as the money supply couldn't keep up with changing rates of economic growth across different economies.