If you accept that the number of people Wall Street employs is bounded, and if you accept that someone else would have this kids' job and probably do comparably

If you accept that the number of people Wall Street employs is bounded, and if you accept that someone else would have this kids' job and probably do comparably at it, then he is not taking from workers pension funds. He's taking from Wall Street money that would have remained in Wall Street (or gone to buy a fancy car or house) and sending it to Africa.