"If you ask me to bus my children, I hope the cops take down your name." - Phil Ochs Love Me, I'm A Liberal
The class arguments are a means to get around using racist arguments. Bill Clinton's vision of America relied on this structure.
De-Facto Reagan Racism re-packaged to fit the needs of white northern racists who earned the right to send their children to better, more wealthy schools.
It's not because the other students they are denying happen to be black, it's because those kids don't have parents paying expensive taxes. It just so happens all the old laws in this country made sure very few black parents could afford to buy houses in these affluent neighborhoods, and those who can are often conveniently refused or ostracized by leading progressive professionals who all have children going to the Ivys.
Their charitable donations "tax breaks" allow them to decide where their funds should go, because they would rather purchase sweaters for puppies than deal with the absolute horror of the government spending their money on the children of minorities.