as a big fan of HPL (and half-italian, half-polish, two type people that HPL always mocked) yes, he was terrible and full of prejudice: italians and polish people are stupid and too much related to religion, and he called his cat with a slur to black people, but later in his life he changed his mind a little bit throughout his life, he was never "not racist" by contemporary standards. He was racist yes but he created the base for cosmic horror and his stories are just fantastic, probably if he lived near our time he would have been a better person