There’s some truth behind some of these political stereotypes.
Liberals are famous for infighting and never being able to come to an agreement on anything. Not that they don’t occasionally find a point of agreement, but voicing any opinion on anything at all is asking for an argument, simply because that’s how it works on that side of the fence. Put any two liberals in a room and they will quickly find something they disagree strongly about. It’s the “diversity is strength” way of looking at things. The differences are laid bare for all too see, because it’s the differences that define the group.
Conservatives are famous for showing a united front. They may disagree about things behind the scenes, certainly, but open disagreement is unseemly (Reagan’s Eleventh Commandment). If they can find enough to get along about, they’ll march forward with that and work out the differences quietly, in private. When it comes to changing their minds, it can appear as if they all change their minds simultaneously, but that isn’t true. There’s still an underlying disagreement, but the working ideological coalition has simply shifted.
So when a conservative encounters a liberal, they get met with arguments, and that seems like hostility. When a liberal encounters a conservative, they get met with the same restrained unified front they get with other conservatives, which seems very creepy in a polite automaton sort of way. From a distance, liberals appear to zealously eat their own (Al Franken), while conservatives appear to welcome monsters (Roy Moore), but really there are disagreements on both sides, just different ways of expressing them.
