Ursula K.Le Guin saw right through JK Rowling early on. The "mean-spirited" description is so on target.
Here is the relevant excerpt from the Guardian interview from 2004.
@LaChasseuse
Right. Rowling tried to identify her villains, House Slytherin, with the Nazis, but at the same time she invented a society whose citizens are all born inescapably into one of four eugenic castes, one of which was "Nazi". The irony is rich.
Chronicles of Earthsea

'I follow where the story takes me...' SF and fantasy author Ursula Le Guin answered readers' questions about anarchism, utopias, Harry Potter, her favourite planets and the best Dr Who

The Guardian
@LaChasseuse She’s talking about the first Harry Potter book, not JK Rowling.