> This may be partly because so many thoughtless people feel qualified to enter a political discussion (e.g., about basic income, or immigration), whereas they couldn't even pretend to understand real-time operating systems or functional programming enough to have an opinion.
This is true, but I suspect the biggest reason is that politics is more prone to Crony Beliefs ( http://www.meltingasphalt.com/crony-beliefs/ ) than almost any other field of discussion.