[...] Nazi holocaust during WW2. Europeans don't have a direct analogue of the American "reparations" debate, but the Germans in particular have been notably open about grappling with their recent history, while people in some other countries seem a lot less interested in cultural introspection or in seeking atonement.
And our German approach to the issue is to self-flagellate at every turn, forever or until the German nation is no more, which cannot come soon enough. All of this being open about historical injustices and grappling with them is a way for historical winners to become losers, and nothing else. Historical injustices are impossible to resolve productively, especially in a moral framework that rejects every kind of group in favor the individual, and even more so now that some groups are re-introduces as acceptable as long as they belong to the canon of historical victims. It leaves no room for the group that once committed a crime but ended up in a dominant position; the only actions they are permitted to take are servitude to their former victims or self-annihilation.
Historical justice is an impossibility, and here a demand for making the impossible happen without even bothering to pretend that there is a mutually beneficial solution is used to weaken and hopefully destroy entire nations. It deserves no legitimacy. It's just culture war, war and the group that lies to itself that it is not war will lose it.
What justice can there be for the blacks, or the jews, or the slavs? Reparations paid and the entire issue settled with finality? Who believes that? Everyone knows reparations are just one step towards reversing historical fortunes. Reversing them, not undoing them or compensating for them - the former winner must now become the loser, must self-efface and self-debase, and having them pay money will satisfy neither the designated victim group nor their advocates.
The group is dead, long live the individual - but as soon as group identities can be wielded as weapons of culture war, they're brought back. A successful individual of the victim group is successful on their own merits, and successful individual of the oppressor group is successful because of privilege. A failure from the victim group is oppressed by the oppressor group, and failure from the oppressor group is to be ridiculed as the individual failure they are. And the groups themselves exist, are more than ephemeral social constructs to be forgotten at the waving of a hand, only when blame is to be assigned to the oppressor group, or when the victim group is marked out to be deserving of reward. In all other cases we are individuals, and groups do not exist.
We can see where this leads. Everyone who can flees the oppressor group. Germans are now Europeans or World Citizens. American Whites are suddenly people-of-color-even-if-not-black-or-at-least-some-new-flavor-of-sexual-minority. And once you thus saved yourself, you too can join the chorus of those demanding that the oppressor group recognize the historical injustices committed against you, and that you are deserving of reparations.
If you give these issues legitimacy but you do not save yourself to some new non-oppressor identity, then you are playing the game wrong and you are fighting the war to lose. What outcome do you expect? What outcome do you see as desirable? What would you even suggest as an actual solution? And do you truly believe those culture warriors would not find some new grounds on which to name your solution an injustice, or insufficient to repair history?