There’s ways to CLEARLY state you enjoy the art, and not the artist. Rereading books you’ve purchased years ago, watching movies you’ve purchased years ago yeah. And yes buying new HP merch does give her money so it is “supporting” her, but there’s only so much you can do. I definitely enjoy HP, I’m not as into it was I was say 2 years ago, but I’ll still interact with fan edits and crap💀
There are a few things that you don’t notice as a kid (racism, antisemitism, fascism to name a /few/) but mostly it’s because JK Rowling is very very VERY transphobic, particularly to trans women. She donates a lot of the money she earns in royalties to anti-trans organizations. I myself enjoy the memories and the movies and Drarry fics but art vs artist is a difficult topic to discuss depending on the person.