I would say technically the point of a prediction market is to predict things in advance of them happening, so I think you might get people who sensibly disagre

I would say technically the point of a prediction market is to predict things in advance of them happening, so I think you might get people who sensibly disagree with this point of view. But in the article it's a little confusing, because the person who did this could only trade IIUC with other people on the same day as the day the figure would be published so the people who traded with them were doing something very ill-advised to start with. I can't see how any of this would have affected people who tried to actually predict the co2 level properly, except that now they don't have a market any more.