I want to caution about reading -isms into authors works. People often don't really know their own stereotyping unless it's pointed out (you, dear reader, probably have some problematic world views that no one has noticed or mentioned...). The fallout afterwards is where the problems exist, when someone doubles down on their viewpoints after being informed of them.
Rowling has clearly done that and is dismissed because of it. I will avoid things that give her a platform, and the original art itself is tainted due to her continued stances; but, back to the general case, just because art might be racist or antisemitic, etc., at the time of creation, if the artist can be convinced that their views are wrong, we should celebrate that -- just with footnotes and context.