Seems like a good reason to figure out some additional soak-the-rich taxes! (Back in the 30s that was a slogan that Americans could rally behind..! Not so much right in the last several decades.)
But it's also disingenuous to claim that none of today's approaches would show up as high income. A lot of old money would be protected still, a lot of new-money would be hit.
Isn't it telling that there was so much massive development of American industry in the post-WWII era and yet there weren't any Musks or Bezos or Gates? A country that had minted tycoons like Getty and Rockefeller and Carnegie stopped for a while. A guy like Howard Hughes was involved in several areas of development but didn't touch the guys who came before him or after him overall...