Whether it’s true in that case or not, it frequently happens that someone will start to act like they disagree with you about everything, because they happen to disagree about a few issues. And that definitely can cause them to do things that they otherwise wouldn’t do, just because you suggest that doing them is a bad idea.
Alternatively, the causal arrow goes in the other direction. People don’t give your practical opinions much weight, but you don’t realize the gulf until you have a flare up about ideological disagreement.
I agree that ideological disagree can lead to lower weight to opinions, but if the gulf is as large as OP described, then I suspect the blow up was a symptom, not a cause.
I know at least a few people who have >90% chance of agreeing with basically anything I say, if they happen to be in a good mood, and almost the same chance of disagreeing, if they happen to be in a bad mood.
Whether it’s true in that case or not, it frequently happens that someone will start to act like they disagree with you about everything, because they happen to disagree about a few issues. And that definitely can cause them to do things that they otherwise wouldn’t do, just because you suggest that doing them is a bad idea.
Alternatively, the causal arrow goes in the other direction. People don’t give your practical opinions much weight, but you don’t realize the gulf until you have a flare up about ideological disagreement.
I agree that ideological disagree can lead to lower weight to opinions, but if the gulf is as large as OP described, then I suspect the blow up was a symptom, not a cause.
I know at least a few people who have >90% chance of agreeing with basically anything I say, if they happen to be in a good mood, and almost the same chance of disagreeing, if they happen to be in a bad mood.
Do they actually mean anything by their (dis)agreement, or it’s just content-free social noises indicating “good, good” or “bad, bad”?