From CNBC:
What do ETFs and Karl Marx have in common?
That may sound like the setup to a corny joke, but for a research team led by Inigo Fraser-Jenkins, it's no laughing matter. In a note boldly titled "The Silent Road to Serfdom: Why Passive Investing Is Worse Than Marxism," the Bernstein investment strategist sets out to prove that the rise of passive investing is a serious problem for the economy as a whole.
The posited problem with predominantly passive capital markets is that they cannot possibly allocate capital efficiently.
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