Goldman Sachs CEO David Solomon demonstrated his social enlightenment in Davos this week by announcing that the white-shoe investment bank would no longer help companies with exclusively white, male boards go public—as long as its boycott doesn’t hurt business too much.

“Starting on July 1 in the U.S. and Europe, we’re not going to take a company public unless there’s at least one diverse board candidate, with a focus on women,” Mr. Solomon said on CNBC Thursday. “We might miss some business, but in the long run, this I think...