There is just one real working prediction market: Polymarket. However, it is currently illegal to use in the US, because of old laws. This can be circumvented with cryptocurrency, but most Americans still won't use such a hack. Which strongly limits the popularity of Polymarket, as US Americans happen to be the people who are most interested in prediction markets.
There are also the prediction ... platforms Metaculus and Manifold, which are legal in the US, since they only use made-up internet points instead of real money. I'm not sure whether this even hurts their accuracy compared to Polymarket though.
If enough people cared, you could probably make the same argument that got sports betting into a place of legality and get at least some subset of prediction markets legalized.
The sportsbook argument was that sports betting involves more than random chance - knowledge of the game, the players, etc. effectively turn it into a matter of skill.
I doubt there are enough interested parties to bother for prediction markets, though.
There are also the prediction ... platforms Metaculus and Manifold, which are legal in the US, since they only use made-up internet points instead of real money. I'm not sure whether this even hurts their accuracy compared to Polymarket though.