The cultural left is against her for being very visibly transphobic (along other things). Additionally religious reactionaries historically don't like the fact her books are inspired by historical witchcraft practices, as pointed out in the meme.

To quote wikipedia's summery:

...Whited asserted in 2024 that Rowling's sometimes "flippant" and "simplistic understanding of gender identity" had permanently changed her "relationship not only with fans, readers, and scholars ... but also with her works themselves".

https://en.wikipedia.org/wiki/Political_views_of_J._K._Rowling#Transgender_issues

She's a huge bigot...

I don't think you can categorise into right or left. I know right-wing people who are gay as an example (they're conservative, but they're not MAGA/Trump/nazi's).

It's really better to categorise as "people who want the community to be better and want everyone to be treated well", and "people who want people to receive different treatment".

JK Rowling is the latter. Trump is the latter too. In general though, in US and Australia, extreme right wing people seem to fit more into the latter.. Minorities can also fit into either category too quite easily

nobody on the left would ever say that someone who does one cool thing is automatically a good person. There's been plenty of asshole artists and overall thing makers in history that have made amazing things

Let's let her speak for herself.