I haven't used these myself, but I read that discussion on betting sites is less emotional and troll-y. Presumably because people are more focused on being actually correct, rather than on ideology.
Example: https://www.predictit.org/
Example: https://www.predictit.org/
I wonder if an HN-like forum with prediction at its core would have legs? I always found the best comments in prediction tournaments at least as interesting as the actual estimates, but none of the platforms really support back-and-forth conversation.
Example https://www.predictit.org/markets/detail/3698/Who-will-win-t...