This seems like a false equivalence. We all have the capacity for great good and great evil. And most of us have probably done very good and occasionally very bad things, objectively speaking.

Framing matters and context too, but some things are just objectively bad in any light. Some are objectively good.

I think that truth (or at least belief in it) underlies why we collectively punish folks perceived as getting away with something that looks undeniably bad. Then add other phenomenon like the bandwagon effect and it can be crushing to the target.