Is it possible the political questions are really a test to see if you have the good sense to avoid bringing controversial politics to work? Maybe they were looking for something along the lines of "Political opinions will differ. I'm more interested in being part of a productive team than having my politics validated."

People are so complicated that most "tests" like this, to see how somebody responds, strike me as useless. You are not in a controlled environment, and pretending you are is foolish. You might get a reaction and presume to know the cause, but it's hard to be sure. Maybe somebody reacts badly to a strong signal that the interviewer doesn't know how to be appropriate and professoonal in an interview.

Strongly agree with your statement, but I still think it is understandable for interviewers to want to know how their interviewee will react in situations that can easily lead to big conflicts. If you reflexively act in a way that escalates in stressful situations, that's useful information in a hiring decision.

I hope people can understand the difference between getting a feel for someone's temperament, vs. getting a feel for their political opinions. I highly doubt that the situation in question was the former and not the latter.

Crucial difference. Only meant to suggest that there is some possibility that the question was probing at temperament. Asking about politics might be used as a method of checking how easy it is to anger someone, since it is a topic that causes many to control of their emotions.

It doesn't really matter. It's very inappropriate. What you're describing is sometimes called a "shit test". A disingenuous request intended to draw out a response to be judged. This has no place in an interview.

I have the good sense to avoid working with people who are playing mind games with me.