I wonder about two things:
1. Legality. Taking bets from Americans has landed other company owners in prison so I always wonder how they handle this on internet based gambling sites.
2. Oracle. Who decides who wins? It looks like it's decided by the company owning the platform. This seems a little dubious but maybe it works with the transparent nature of many of these sort of bets. Of course, they could always be in dispute.
The only information I could find on the oracle: https://dyor-crypto.fandom.com/wiki/Polymarket#Oracle_Method...