@DanHomerick I guess I don't see the divide between betting on an outcome (or multiple outcomes if you want) and a prediction market.
@JonWharf maybe it's just in my head, but let me try to explain the divide as I see it. Sorry if this is a bit long, I'm kind of thinking through my opinion by writing about it.
Starting with an extreme example, suppose the question was to pick the exact day. Completely unknowable, so placing a YES position is just like picking lotto numbers. Each choice has a probability too close to zero. At the other extreme, you could have a question like "Will the sun rise tomorrow?" which has the probability too close to 1.0 to be interesting.
This market isn't nearly as extreme of course, but we're still trying to pick a specific year for something that is potentially a long ways out. The likelihood of each choice isn't very high, so you kind of have to spread a bunch of bets around and hope that one of them will hit.
Whereas with a well-structured market (IMO), you shouldn't need to toss bets out like positions on a roulette wheel. You should be asking instead, "is it more or less likely than $current_value?" Is there upcoming news that is going to make everyone change their minds and shuffle their estimates?
I think a series of "before 2025", "before 2026", "before 2027" style choices give that. The too early and too late choices quickly get driven to ~0 and ~100 and all the action happens in the middle. You get a nice curve. It's more informative about people's opinons, and more interesting to participate in.
@DanHomerick thanks for the response. I think that (subconsciously) I was trying to push participants to be non-conservative in their choice(s). If I see a bet structured in the way you suggest, the tendency is to drift towards a more inclusive option, whereas you don't have that "safety" in this setup. Of course that riskiness may make my question less attractive to the crowds, which will be a different lesson for me.
@JonWharf As a datapoint, I don't feel inclined to bet on this market, but if it was a "before [year]" market I would be more interested. I don't like betting a large number of small probabilities, even if I know that logically it's basically the same. It's just not how the probabilities are arranged in my head. I don't go "will it happen in 2035?", it's more like, "by when is it likely to have happened?"