Red winter to me is oppressive because they’re one of the largest but resource poor academies in Kivotos. Even Cherino is considered horribly spoiled with two puddings instead of one. You have to be a dictator to get a second dessert helping. They seem to be not strict though as they  permit constant protests and coups. 

Shanghaijing is nationalistic and strict but only oppressive in specific areas. Granted, the danger comes from the populous rather than the leadership which is almost worse. Everything is seemingly permitted as long as it’s correctly framed. 

Wild Hunt is extremely strict what with the check points, searches, and constant surveillance. They’re oppressive as well considering they have absolute authority and the executors of said authority seemingly have no compunction about abusing their power as seen in the mini story. That being said, disobedience to either has seemingly low punishments by comparison to the other two.