Just a few hours ago the social media algorithm gods decided to show me a video from an autistic woman who was basically saying exactly this. “Hey, my special interest is HP, but y’all need to understand that this isn’t a ‘Death of the Author’ situation, Rowling is literally funding anti-trans bigotry and we need to not be complicit in that. I don’t care if you pirate her stuff or buy second-hand or only read fanfiction, but don’t give her money.” Personally, I try to stay away even from secondhand consumption of her stuff because I just don’t care about it, and I think it’s at least best to avoid giving any positive or neutral (which to me includes any film/book review that isn’t primarily focused on highlighting Rowling’s bigotry, even if it’s largely negative on the storytelling, prose, or dialogue) attention to the media in her franchise, but I can understand some people have a much stronger attachment to it and want to minimise the harm they cause by continuing to watch through pirated means.

But it’s not really my place (as a cishet white dude) to say whether or not that’s the correct choice for other people to make, so I won’t judge any choice anyone makes that doesn’t involve giving her money through purchasing official products.