As a neutral independent, I don't believe that any political side is truly more "compassionate" than the other, though statistically, disagreeable and less empathetic people tend to be right wing, but correlation does not imply causation. Rather, each side selectively empathizes with a particular group to fit their worldview. For example, when it comes to social welfare, the right is sympathetic towards those who are forced to pay for those programs that do not benefit them, while the left is sympathetic towards those who are in bad condition because the right view it as deserved whereas the left views it as injustice. Imagine working hard to accumulate wealth, staying up for hours and working weekends, and then lazy people who watch tv all day wants a cut of what you sow. You don't sympathize with that?
Preference towards groups necessarily leads to certain groups being "left out." I think the rise of "incels" is a perfect example. There are millions of poor lonely males in a shitty condition, and yet they're insulted for their natural feelings of sexual frustration, and told that they're privileged. You think the left gives a fuck about them? Fuck no, everything is caused by "toxic masculinity." Furthermore, certain issues, such as height discrimination are completely left out (less than 3% of top 500 CEOs are under 5'7"). Even if you're a short ugly fat guy, you're still privileged. Where is the "compassion" towards them?
It's funny to me how you can't put yourself in their shoes and see why they would hate the left. Certainly, I can see why women or trannies or whatever would hate the right, because I view this as a battle of two sides with competing interests, rather than right or wrong like you do. Morality blinds your judgement. Both sides view the other sides view each other cynically, and their problems as unjustified, not just the right.
Furthermore, empathy usually brings hatred towards those who are blamed for the cause of the grief. For example, empathy for illegal immigrants lead to hatred towards immigration enforcement and attacks on them and even their families. You don't see republicans harassing democrats at restaurants, damaging property, disrupting events, and whatnot. Look at how empathetic antifa and their supporters are to their victims.