If a person had major accomplishments in the past and adhered to their current moral code, why should they be denied a place in history because moral codes changed? You are simply trying to erase history to justify some misguided feeling of moral superiority.
Every generation imagines itself to be the culmination point of history, rather than merely one more link in the chain of the historical process. The modern bourgeois liberals, however, seem to be the first generation to have elevated this conceit into an ideology.
You realize the future will judge you the same way and find you wanting? Current moral codes will be seen as barbaric.
All moral codes are historically and socially conditioned, and are therefore bullshit to a greater or a lesser degree. But what else can be do except judge the past by the moral code of the present? It is, after all, possible to see how it could be that that person would have that moral attitude at that point in history, but still condemn it as being 'immoral' and unacceptable. By celebrating these people, we are implicitly endorsing
their outmoded moral code as being acceptable or even as something to aspire towards. But history has moved on, and we should move on with it.
Should they erase you?
Not erase, but certainly not glorify. It may have been necessary to glorify murderers, rapists and thieves in order to advance the cause of the British Empire (in fact, I would submit that glorifying such people is
necessary if one's aim is to increase the power and influence of one's own nation-state or empire). But once the empire is gone, why continue with the lies?
"Politics is the art of looking for trouble, finding it everywhere, diagnosing it incorrectly and applying the wrong remedies." - Marx (Groucho)