> to fix the sins of those who are long since dead
A good number of land right issues and acts of racism began with those long dead and continued forward under the actions of generations that followed, perpetuated in some form by some still living.
In a US context there are still current acts of administration that impact native title and rights to reservations that are current and contentious.
I mean, we should try where it's possible and reasonable and the impact is ongoing. When a bunch of long dead people passed a law saying that women can't own property we were right to later correct that sin. We shouldn't allow ourselves to be trapped by the horrible choices of the dead. We just have to be careful about when and how we try to correct the wrongs of the past.
But things stolen with violence or threat of violence, should probably be returned (if they want it returned). While we shouldn't hold children responsible for the actions of our parents, we can also be better than our parents and return things we know aren't rightfully ours.
Off-topic, but you're probably one of the top 3 persons in the world with the most similar first+last name as myself, with a Levenshtein Distance of only 6 :)