While I'm on the subject of JK Rowling, I want to add that this pervasive idea floating around that "no one asked her" or "she's just cash grabbing, she needs to stop talking!" each time she adds something to her world or write something new within it, is just as cringy and idiotic as other type of vitriol leveled at her.
First because, again, no one levels that kind of bullshit at other creators. No one is crying foul about Pullman writing within the HDM universe, nor at GRRM for writing side projects within ASOIF before even finishing the main story (granted, he does get criticisms for not writing the end at all, but that's a legitimate thing to say, the vitriol isn't about him writing something else and expending per see which makes a difference here). Others are allowed to expend, to add, even to sell their intellectual property to big studios to plunder without much criticism, but god forbid JKR says Hermione loved math in middle school on Twitter. They act like for her to be legitimate as "HP's owner" she must be perfect and needs to ask "permission" before having fun with it just for the sake of it. I've never seen any other creator treated that way to THAT extent, and if I'm wrong, please show it to me, but I don't think you'll be able to.
Secondly because in what God forsaken universe do you live in where this Fandom DIDN'T ask? We did ask. We did nothing but ask! Are you all zoomers who didn't grow up during the madness or do you have that much of a short term memory?
Back in 2007 after DH was published, people kept asking her over and over again; "Please Jo write Hogwarts: A History", "I hope she does a Marauders prequel!", "Jo, what is Neville's wand core?", "it would be so cool to know what the next Gen is up to" and so on and so forth. This is why Pottermore originally became a thing in the first place, a website which she labeled a gift to the readers at the start and where she released the unpublished material that didn't make it into the novels for FREE.
But now that you don't like everything that she's said and that it doesn't entirely conform to your imagination, ideas and American-centred calvinist politics, you're acting like toddlers throwing temper tantrums for not getting exactly what you want?
A bunch of you are acting so entitled it's not even funny, JK Rowling is one of the huge reason why Fandom culture is allowed to be what it is today, she's was one of the first big name authors to publicly say that people should be allowed to play in her sandbox, with the toys she brought in, even actively encouraged it. But now here you are acting like you own the sandbox and she ought to ask you before participating if she wants to.
Honestly grow up and move on. Your vitriol is exhausting and immature.