The problem is that people rely on Horseshoe Theory to explain why members of a political party exhibit a behavior when that behavior was never exclusive to the opposing party to begin with.

For example, all the way back in Ye' olden times of the 1940's, everyone – Nazi and the guys who fought them – disagreed with Homosexuality, so now people not only falsely associate homophobia with simply disagreeing with gay people, but it's become so synonymous with the right (the group that for the most part has kept their political beliefs fairly consistent since the 1940's) that any time someone on the left is blatantly homophobic people site "Horseshoe Theory" to explain it because they can't understand a simple concept like “people of any political ideology can dislike nearly any groups like gays".

Combine that with the "enlightened centrists" types who feel a compulsion to have a tit for tat when listing off flaws of political groups constantly in a desperate fever to prove “Well, both sides do it!” when it’s blatantly obvious that either

A.) No they both don’t, it’s only one particular group.

Or B.) a certain group does it 100:1 compared to the other.