I think the issue is that a lot of the fan base got into it before the mold got to Rowling. It's hard to pull away, and easy to look past the issues like that Victor Krum sentence, or having the Irish kid be the one always blowing up, or (insert other item that can reasonably be viewed as a stereotype when you remove your rose colored glasses).

Especially if you were part of the midnight releases for the books or movies (do they even do those anymore?).

Most especially when viewed in the light that most people are detached from this discourse entirely. Old fans likely view the series through their eyes when they were younger.

That being said, I think it's morally important to not put money into it. If you hold it close to your heart already: there's no need to buy more HP merch. If you don't already own the books: use a library or borrow from a friend if you feel the urge to read it. If you don't like it or want to give people alternatives in the genre: advertise alternatives without mentioning HP at all.

I'm not rationalizing this as acceptable. I'm just taking time to talk about the mindset. It's similar to the mindset that people have when it comes to other social issues related to our purchase habits, and I think that's the reason why it's important to understand.