Which you could do if one of your grandparents had a special status group identity. For example, many of the Americans who declare themselves Irish have even less connection to Ireland than you have to the Netherlands. One Irish ancestor 200 years ago? Close enough! Identity politics isn't rational.
Racism also isn't rational, so it too doesn't need to make sense. Right now, it's still at the stage where any ancestry that's "black" makes a person "black". The old "one drop" standard beloved of pro-"white", anti-"white" and pro-"black" racists. Of course, that will change as fashionable racists gain power. Any ideology of racism contains the idea of racial purity, so the only thing suppressing it is the idea of "white" being a common enemy. In time, the targetting will turn on people who are "not black enough". The beginnings of that already exist and they already have a (victim-blaming, unsurprisingly) name for it - "colorism".
