Says you. Many/most thinking people disagree.
Because there's no way of defining "Black". Or "White". Or "Person of Color". There's not even a generally agreed upon definition - even among experts - for "Race".
Perhaps you mean Black is just short for "American of African heritage"? Well, go back far enough and Americans are all that. Americans are all Black. (Good news: reparations for all.)
A very dark-skinned Fijian-American I asked said he's not black. But would he refuse a special government program for blacks? No. Would the government withhold special support for this dark-skinned fellow? No.
The idiot Kamala Harris claims she's "black". And while we're at it, are the Chinese "people of color"? What about the half-Chinese, half-white? Is it ok to say "yellow-skinned"? Says who?
Now there are machines that measure skin color. Why not add these to the mix. A Black-o-meter in every public space. A People-of-Color device to sort out who gets what special status. Swarthy Mediterraneans: keep working on that tan. Albinos may be SOL.
Again, race-baiting is a distraction for the feeble-minded. This includes Scott Adams who couldn't identify "Black" or "White" any better than the rest of us.