This article is talking about the labor-shareholder profit split. It's absolutely relevant to point out the opportunities normal people have for becoming shareholders. stockpile.com let's you buy fractional shares (no longer need 2k to buy a share of amazon) for a 99 cent commission. You can get commission free ETF's from Schwab with a couple hundred $ account minimum.
Arguing that most workers are so strapped for cash that they literally cannot set aside a few bucks to invest -- and not only that -- that arguments even hinting at such a thing should not even be said out loud, is mind boggling.