Because one of the most basic things you need to help your children learn while they develop is the difference between discomfort and danger. Guilt is uncomfortable, not dangerous.

Maybe, but even so, until they have learned that difference, they won't know that difference, so making them feel guilty will harm them. Kids need to be taught about sticks and stones vs. words, but even that doesn't get to guilt and shame, because insults may be unwarranted. But with racial guilt, the assumption is that the guilt is warranted, so young children, who don't have the frontal lobe development to see guilt as a reason to be better, may in fact be harmed by exposure to their own "guilt" as beneficiaries of systemic unfairness.

Why shouldn't a young child be guilty about every bit of unfairness he or she enjoys? A roof over one's head is unfair to those who don't have them. Why should a child be able to share a bedroom - in a house with bedrooms - with only one sibling when children elsewhere have no houses? Why should my kid have shoes if someone else's kids don't have them? Kids can't differentiate among unfairnesses, because, wait for it, THEY ARE CHILDREN.

How about you give the kids a chance to GROW THE FUCK UP before you fill their brains with things they can't process? Children are not little adults. They need to learn to process unfairness before they are told they are beneficiaries of it. I understand that's not fair to Black kids, who learn about racism through hard experience, but the lesson there is that experience is, indeed, a very destructive way to learn that lesson. To visit the same misfortune on White children "to be fair" is just two wrongs making a right, which is pretty much what self-styled "anti-racism" is about.