Remembering people for historical deeds isn't 'celebrating' them at all - or are you suggesting we should brush all the people who have, by modern standards, populist consensus or just what 'Karen off of facebook thinks' acted badly at some point in their lives - under the rug of time and never mention them again??
I never said laws were retrospective.
He mentioned "guilt in a criminal conspiracy" and I agreed.
No one can change facts. What you can do is change a narrative. I don't argue with slavers or racists being celebrated in their time, I argue with them being celebrated now.
Or maybe we should remember them for everything they did, so that we can have a clear measure of what good, bad and indifferent looks like in the historical record? Why stop at Statues - maybe move on to sanitising pictures & books as well, removing any inconveniences that do not conform to modern standards so people that come after us don't have to see how 'bad' we all were through history. Yer, that'd work.