It's easy for people to forget that being overly emotionally invested in their argument can cloud their judgement. Most of us do it at some point, I am not immune, but if someone has any reasonability in them then it can actually help at least reflect on why they are championing their position. They may not change their position, but they might try to form a better argument that has more solid grounds.

After all, sometimes an emotional reaction comes from a logical basis, but the emotion can avalanche and then the logical underpinnings get swept away so they don't get re-evaluated the way they should.