The pardoning of an "indecent" act.

[TigerLover]

But the people who are "pardoning" now are very much alive.

A pardoning is a legal thing simply absolving someone of the legal consequences of a crime. It in no way implies that the people doing the pardoning are possible for the sentencing in the first place.

An apology on the other hand does imply fault. The person (or people) who have wronged you are the ones who should apologise for that wrong. If I tread on your toe then of course I will apologise. However if the person who happened to have the same job as me 50 years ago stands on your toe then no i'm not apologising, why would I, that'd be absurd and disingenuous.