Gold is a great thing to sew into your garments if you're a Jewish family in Vienna in 1939, but I think civilized people don't buy gold, they invest in productive businesses.
A banker who is allowed to borrow money at X and loan it out at X plus Y will just go crazy and do too much of it if the civilization doesn't have rules that prevent it.
When someone takes their existing business and tries to transform it into something else - they fail. In technology that is often the case. Look at Kodak: it was the dominant imaging company in the world. They did fabulously during the great depression, but then wiped out the shareholders because of technological change.
There's more honor in investment management than in investment banking.
Wall Street has too much wealth and political power.