Not only did you miss the point of the conversation entirely, you're attacking a point I explicitly addressed in my comment. I well understand how the system works, ggps comment had me confused about their perspective.
I didn’t miss the point at all. Once you’re in, unless you want to sell your stake, you’re in. But the entire point is that at the time of your bet, you’re taking a position that’s inherently disadvantaged. If there was any more EV to be gained, people with more money than you would have exhausted it. So without insider information, you’re flipping a coin but the house takes a cut.
>if there was any more EV to be gained, people with more money than you would have exhausted it
In a perfect market that everyone participates in and in which everyone has perfect information, but not down here in messy reality. Your logic would have you you seeing a dollar on the ground and without further investigation go "Oh that can't be real, if it were someone would have picked it up already!" Or refusing to play chess against anyone because Magnus Carlsen could beat you.
The stock market isn't perfect and not everyone participates in it, and the data is extraordinarily clear that essentially nobody is capable of extracting a durable edge. Of the people who do beat the market in a given year, those who beat the market the next year appear to follow the exact same distribution as the market as a whole.
Prediction markets are worse, both on the surface and by the actual statistics. The house takes an enormous cut, and then you have the issue of trading against insiders. Only an absolute rube would put money into a market rife with insiders, when they don't have comparable information. And the statistics bear this out. Something like 80% of all profits are captured by the top 1% of profitable users, which are only 30% of the total user base.
Anyone who thinks they will consistently make sound bets in these platforms without actually having private knowledge is a complete fool.