Thing is, prediction markets tend to be gamed by people who bet large amounts of money. I used a (play money) prediction market platform before and there was literally a "markets that get easily gamed by whales" section on the website.
I don't disagree that the one french dude betting 30M on Trump on polymarket showed that there isn't enough liquidity in such markets for such distortions to be corrected, but whalebait on Manifold is not really related.