I've only said that there appeared to me to be enough of a chance of him being one that I wouldn't risk spending time, effort, and emotional capital engaging him in debate over those topics.
Just raising the possibility of somebody being part of a low-status group is often enough to damage their image in the eyes of others, and many conversational norms treat raising such a possibility as the same thing as an outright accusation - for good reason. (Bullies would love the freedom to go around implying bad things about people while facing no risk of censure.)
I've just paid five Karma to answer this: all I wanted was for Imm to understand where I came from when I dropped the discussion, and to show him that it is not an entirely irrational train of thought that would draw people away from discussing these topics with him. I failed to consider the fact that I was talking to him in public, and that what I was saying had implications on a level above that of the discussion. From what I've seen so far, I gather that I should have either ignored him outright without saying anything at all (perhaps it would have looked like I had forgotten the discussion altogether?) or continued via PM as soon as those topics were broached.
Now, it is said we all here pride ourselves on our intelligence, rationality, and moral sense. It is also said, however, that we are a fiercely independent bunch, and that we can let this pride of ours get the better of us. There have also been comments that the live communities that appear at meetups provide much more positive interactions than what goes on on this site's discussions; this might merit further investigation.
My point is; we've done a lot of research on how to do proper ethical and metaethical calculations, and on how to achieve self-empowerment and deal with our own akrasia, which is awesome. We've also done some work on matters of gender equality, which is very positive as well. But I haven't seen us do anything about the basic details of human interaction, what one would call "politeness" and "basic human decency". And I think it might be useful if we started tackling these, for our own sakes, that of those who surround us, and that of easing our mission along, which is, as I understand it so far, to save the world (from existential risk (at the hands of (unfriendly and self-modifying) artificial intelligence))).
What inspired me to propose this post was a video I just saw from Hank Green of the famed and fabled vlogbrothers. I hold these two individuals in very high esteem, and I would expect many here to share my feelings about them, on account of their values and sensibilities largely overlapping with ours; namely the sense that intelligence, knowledge and curiosity are awesome, and that intellectuals ought to use their power to help improve themselves and the world around them.
Here it is; I hope you enjoy it