Anecdotal of course, but in my limited experience, I've seen plenty of superiority complexes and generally assholery, but no Linus fanboyism. I don't like it, but to me it seems like a perfectly unsurprising aspect of the software industry.
Your idea (my interpretation) that the industry mostly consists of people having productive discussions seems more off base. Yes, that's the way it should be, and usually is on HN and similar forums, but out in the larger real world, arrogance, superiority, etc are the order of the day.
Yes, I know the real world sucks. In light of that, let's try not to actively make it worse. Applying Hanlon's Razor aggressively is the easiest thing we can do. And don't forget the selection bias from the fact that jerks are more likely to make themselves noticed than rational people.
Your idea (my interpretation) that the industry mostly consists of people having productive discussions seems more off base. Yes, that's the way it should be, and usually is on HN and similar forums, but out in the larger real world, arrogance, superiority, etc are the order of the day.