It's a relatively compelling argument, but I'm not convinced that the reality is as "zero-summy" as you're suggesting for a few reasons (off the top of my head):
a) I'm not convinced that it's as difficult/expensive to spread FUD as it is to spread whatever the opposite of FUD is.
b) I'm not convinced that different classes of investors respond in the same ways to FUD and whatever the opposite of FUD is.
c) I'm not convinced that different classes of investors have the same access to tools that allow them to "buy long" and "sell short". This may be on the way to changing, but currently even e.g. Robinhood does not support short selling.
I say "not convinced" because I honestly don't think I have the answer to this, but if the answers to the above questions go a certain way that I think is fairly plausible, it seems that the net effects would include a disproportionate burden on disruptive/innovative ventures that are especially vulnerable to FUD, and an increase in wealth inequality as capital flows to more sophisticated investors. Neither of those things are great.
a) I'm not convinced that it's as difficult/expensive to spread FUD as it is to spread whatever the opposite of FUD is.
b) I'm not convinced that different classes of investors respond in the same ways to FUD and whatever the opposite of FUD is.
c) I'm not convinced that different classes of investors have the same access to tools that allow them to "buy long" and "sell short". This may be on the way to changing, but currently even e.g. Robinhood does not support short selling.
I say "not convinced" because I honestly don't think I have the answer to this, but if the answers to the above questions go a certain way that I think is fairly plausible, it seems that the net effects would include a disproportionate burden on disruptive/innovative ventures that are especially vulnerable to FUD, and an increase in wealth inequality as capital flows to more sophisticated investors. Neither of those things are great.