I'm sorry if my post sounded uncaring towards people who are claustrophobic or otherwise afraid of flying, as that was certainly not my intent. I can't imagine the additional stress it must cause. I've never observed a passenger asking to be removed from a flight, so I have no way of estimating how common it is.

And I wasn't buying into the theory that it was a dry run or anything malicious.

My assumptions - and they were only that - were (a) that inexperienced fliers often overpack both a carry-on bag and checked baggage, and (b) that people who fly often might be less likely to experience a claustrophobic attack than someone flying for the first time. I don't consider these absolutes, just probabilities.

In my comments above, I made no mention of the passenger's ethnicity, and honestly, I was already thinking "yeah, that's a bit unusual" before I got to the last paragraph. So I would have thought "yeah, that's a bit unusual" if it was anyone.

And "yeah, that's a bit unusual" is all I meant. As I said above, not "suspicious", not "dangerous", just "odd." In the OP's position, I imagine I would've thought to myself, "huh, it's a bit strange that a (presumably) infrequent flyer has no (apparent) carry-on bag" and then forgotten about it. I wouldn't have mentioned it to the passenger next to me, and if I'd asked the FA whether they'd be removing his checked bag, it would have been out of concern for a missed connection.