Prediction markets are a way of effectively placing a "bounty" on something you would like to happen. Or capitalizing on one of these existing bounties because you're able to affect the result. It's a way to commodify power (and information of course, which is what these platforms bill themselves for), converting it into money, which can you can build further power with.
So it's not surprising someone would be against restricting gambling. The hard part is to how the gov should do it. But it's not government's job to please every single person.