Well in the case of last name unless those dead peoples was the last one standing with the surname there is always the possibility of a descendant or someone from a different branch of the family name tree commiting bad things.
Add to that some people sometimes decide to give a famouse surname as a firstname for their kids. There is a non negligible number of people sporting the Lafayette, Napoleon, Lincoln as first name for example that could do something bad anytime.
Well, it can work out OK if one particular person has a strong enough association with the name. Lincoln is a great example. It seems unlikely that anyone with that name will become so infamous as to tarnish it. The voters of Lincoln, Nebraska or the board of the Ford Motor Company (owners of the Lincoln automotive brand) are pretty safe from needing to rename those things.
There’s still the risk of a sudden culture shift where e.g. the San Francisco school board decides it’s no longer acceptable to have a high school named after Abraham Lincoln.
