Do the "plenty" of people have an issue with you having a German ethnicity? How so?
> And that I owe them money and should "check my privilege" because of it.
You are conflating different things here.
"Reparations" aren't a way to funnel money from "you" to "black people". That's another oversimplification, akin to saying that Medicare is about taking from richer people to put money into poor people's pockets.
"Privilege" has more to do with the colour of your skin, than your ethnic background.