To me there would seem to be a difference based on someone’s primary occupation and achievement.
Obviously a Nazi leader etc … is primarily involved with genocide.
Washington etc primarily rebelled against the UK. owning slaves – independent of what was accepted at that time – was secondary.
BTw as a patriotic Englishman I would legally try and remove every statue of Washington anyway. He was a real moired be’Malchus and most definitely chayev missa.