I am a big fan of Grant Morrison's writing. Morrison is a staunch vegetarian and opposed to animal testing under any circumstances. These are themes he's explored in a variety of his works and they've not come up in other creations as well. I disagree with him on these issues as I enjoy meat and feel animal testing can be necessary for life-saving drugs. There are times you can separate him from his work, and times you can't as easily. Overall I agreed with Morrison on a number of things, so our differences don't bug me as us. For a starker example, some folk love the works of Orson Scott Card. Card is horrendously homophobic, but it is not readily evident in his works. This results in some people being able to separate him from his works, and others struggling to do so and avoiding it.
Millions of people are at a crossroads where they have to decide whether they can separate Rowling from her, "Harry Potter," creations, or can't. There is no right or wrong answer as it is a personal choice. I myself don't really have a dog in this fight--I only ever watched the first movie and could barely finish the fourth book due to it being dull, looked at how massive the fifth one was, and said, "Screw it." While I may not be as committed to Harry Potter and his wizarding World, many adore it, and they have my sympathies while they struggle to separate Rowling from her work. If they can, that's great, if they too just say, "Screw it," and quit being fans, that is alright as well. I've had some creators I follow who I agree with on almost everything and others where I at times need to separate them from their works (as well as ones that clearly was impossible to do so). Transwomen are Women and Transmen are Men. Rowling is just too ignorant to realize this. At least Harry Potter himself, Daniel Radcliffe, knows what's up--that's an encouraging note to end on.