I think these hard line stances do more harm than good.
My wife and I are active in not supporting any new things, but to talk about how you think it's morally wrong to even talk about the franchise is going to alienate a ton of people.
I feel fine talking about it, and the memories I had with it. Because everyone I surround myself with is completely aligned that Harry Potter was meaningful when we were kids and also JK Rowling is a complete fucking asshat.
This sort of purity testing has got to stop. If mentioning the name of Harry Potter marks someone as a transphobe who is equally as bad as politicians actively stripping them of their rights... The movement will never build a coalition.
Saying that financially supporting JK Rowling is actively harming the trans community is a reasonable argument. Saying that talking about Harry Potter, even if you note that JK Rowling sucks, makes you an outright transphobe is not reasonable to me.