I think GP is saying that, in principle, the UMA token holders can resolve a dispute any way they see fit, even if in practice it's resolved according to the rules. At the end of the day there is someone who has to arbitrate 'truth' for the purposes of payout.

I understand that. What I'm saying is that resolution is only relevant to bettors. It doesn't affect anyone using Polymarket as a passive information source, because nobody is updating their world view based on the resolution of a market, they are updating their world view based on the price action. The price action follows the expected resolution, not the actual resolution.

Even if someone were to game resolution to make a market resolve the wrong way, it wouldn't affect how the market priced the probabilities in the time before the resolution.

it's an imperfect system, but UMA decisions can also be disputed again, up to two times iirc, which moves the dispute/decision to a different group of UMA whales. tbh, i think this is as good as it gets – unless you stay out of this completely.