It's worse in western countries because we like to pretend that we are superior to the "real" authoritarian regimes. Our governments do the same bs but under the veil of "western values".
Negative partisanship is the major driver in most politics because, again, the State fails to provide for the citizens, without fail, in every system, if it would infringe upon the ability of the State to amass/maintain power. It's easier to say "at least I'm not that guy" as you trample on the populous, so we agree that everyone loves a scapegoat. I can do plenty of nuance, but you started at generalizations and I was refuting that first as that's all I have to go on here.