To be clear - the exact problem is that you are proposing excluding specific speakers (Hanania, Hsu, Hanson, the Collinses, etc) - who I find valuable to various degrees, not ideas. If Manifest issued a notice that it was not a venue to discuss IQ or heritability, that seems much more reasonable than excluding these thinkers.
(Why do Hanson and Hanania need to be speakers? They are the foremost advocates of prediction markets on the Right. Their support would be incredibly important in building a cross-party coalition).
As a right-wing person sympathetic to many EA ideals, I'm surprised when I read these posts about how we need to exclude these people to make attendees comfortable. In fact, excluding these people - who I find incredibly smart, reasonable, and valuable - would make me (and I'm sure many of my friends on the Right) extremely uncomfortable.
It seems like you are referring to Richard Hanania - who has been invited twice. I suspect that he was invited because Hanania has been an outspoken advocate of prediction markets. I find it highly doubtful that Hanania has, on net, pushed more people away from Manifest (and prediction markets) than been a draw to them attending.
(1) fetal anesthesia as a cause area intuitively belongs with 'animal welfare' rather than 'global health & development', even though fetuses are human.
It seems like about half the country disagrees with that intuition?