As the saying goes, one move harms both sides. Besides Polymarket, DeFiLlama has also halved the trading volume for another on-chain settled Opinion. Simply put, Paradigm's logic suggests that in an OrderFilled event, both MakerAmountFilled + TakerAmountFilled might appear simultaneously, meaning the Maker + Taker amounts in a single trade are summed up, resulting in double the trading volume. Why isn’t Kalshi affected by this? Because Kalshi doesn’t operate with on-chain contract logic. Its data sources come entirely from self-reports and provided APIs, fundamentally eliminating the possibility of external verification. Compared to trading volume, focusing on open interest, fees, and real-world impact is much more reliable.