Doesn't every country, community, religion or large organised group have an unacceptable past?
Cannot think of one that doesn't.
I am more concerned about those countries that have unacceptable presents, like the Chinese, especially the current treatment of thr Uighurs, of the democracy movement in Hong Kong, and general montoring of their period so no one dare step otu of line, Then there is the Gulf States where arrest without trial, torture and execution for little or no reason is common. I could then start on Russia, several of the Central Asian states, Hungary, numerous African States.
I am not defending anything that happened in the UK, nor am I blind to it, but I find this self-flagellation and what appears the pleasure people seem to get from rolling in the mud of our shame, i find really rather unpleasant.
You can admit your past and face up to it, but much more importantly learn from it and fight it now, but wrapping round you proudly like a cloak I find distinctly peculiar.