Prediction markets are betting markets, and without any usefulness.
Whatever they say on outcomes of elections is merely a reflection of existing aggregated polling and odds; there is no unique discovery of information. The "wisdom of the masses" is nothing more than everyone looking at the polls and aggregated polling.
They are not "futures" markets; they have nothing tangible underlying their bets, thus making "price discovery" a thing. The financial nomenclature used is nothing but BS attempting to avoid state regulation.
Don't overthink this shit.