It's OK, I didn't have it in cache either, I just remembered "people like Robin Hanson have said insider trading on prediction markets is a feature not a bug" and GPT5 tracked it down for me. :)
Apparently there's also something about the duration of a White House press conference where the press secretary may have been deliberately helping some people?
I continue to think prediction markets are potentially extremely useful and valuable, but I feel like there's a huge conceptual muddle about why people would (1) care about an outcome of a market and (2) be willing to bet on the outcome of a market. And perhaps (3) whom else they would be happy or unhappy to have participating in the market with them. I doubt people will be super-content with prediction markets until those issues are a bit clearer for more participants in any given market. (And I don't know exactly how we can make them so.)
I could go either way on prediction markets but I don't think the dilemma here is all that complicated. I think most people interacting with them are just valorizing gambling, and want a Nevada Gaming Commission to step in and make sure that the games are fair. They're not supposed to be fair! They're supposed to predict! It's in the name!
