For me Hajaj bin yousef was a butcher, an evil ruler and wrath of Allah on muslims. Discussed him and his ‘innovation’ some years ago here
Now Sunni have a policy of not cursing anyone from Islamic history. Which is excellent policy in principle :k:. because there is chances of error. But this policy had its side effects that scholars and common muslim refrain from criticising historical figures of early days of Islam. Thus they hardly form any negative opinion about anyone. This is partly ok but the dark side is that they dont allow anyone to investigate their negative traits and try to hide them. Which is wrong IMO.
We should call a spade a spade. If Amir Muawiya started that evil practice then he did a terrible thing. There is no excuse that he was a sahabi. Ummeyed rulers were generally bad ruler except few commanders ( Ammad-uddin Muhammad aka Muhammad bin Qasim , Tariq bin zayad etc )
and ofcourse Hazrat Umar bin abdul Aziz (May Allah be pleased with him )