Wealth envy ...sadly. pretty common here
Your reply to dumbass who likely has no wealth or children was spot on
I know a few very wealthy, though not billionaires. They are the same way. They all seem positively infected with a kind of abortion-MANIA. Not merely pro-choice, but avid haters of the unborn.
As CS Lewis said, "beyond my imagination." I can imagine a lot of temptation, but can't imagine why great wealth would affect people in such a way.