The Venn diagram of people who have deep understanding of capital markets and people who like betting on stuff will have non-negligible overlap. Read some of the stories about Wall Street, especially from before it was all algorithms. Moreover, evidence of apparent insider trading on Polymarket, specifically for OpenAI, has already been shared on HN. Sounds pretty crazy to me to suggest that those odds can't tell us anything about the true probabilities. What's your reasoning?