Not that it matters at this point, but I saw somewhere that he had remorse for his racism later in life. Is this true?

Keep in mind he died at 46, and at best went from “extremely racist” to “very racist.” His political views change, and I have always had a bit of a chuckle on his original assumptions:

As a result of the Great Depression, Lovecraft reexamined his political views. Initially, he thought that affluent people would take on the characteristics of his ideal aristocracy and solve America’s problems. When this did not occur, he became a socialist.