Again, it is about values. Political stance is defined by values. Some politival instances are incompatible with some values. For them, not sharing certain values is a break dealer.

Take it to the extreme, "american psico", he was charming and hot except for being a murderer. Well, from the other person point of view, certain political instances means supporting things that they find horrifying, so it is an instant modkilling. It is not trivial at all.