Historical figures under review

I wonder what is the limit when we judge personalities from the past with modern standards. I have listened to return of onate foot , a podcast by 99p Invisible, in which they explain the role that that particular conquistador has in New Mexico, USA. That person was cruel to the point that it was banished by his own contemporaries.

I wonder where is the limit when judging personalities with the moral of another time. Is there someone who can survive a thorough scrutiny? One figure that is also under scrutiny is that of Columbus. Even in Argentina they removed a statue from behind Casa Rosada. This had an impact on the Italian community of the country.