I just cannot imagine this series not bombing. Rowling's name has become complete poison. Every single thing she's had a hand in since she went full Voldemort has bombed. The only success was that video game, which they repeatedly stressed she had no involvement in, put the character Sirona Ryan which probably made her furious, lets you just barge into whatever bathroom you want without asking because there might be treasure chests in there, just like I do in real life, and the game is honestly so good that it probably would have been a success no matter what IP it tied to. So with that money they went and made a stupid fucking Quidditch game which was an enormous failure so I think all the people who were crying HL didn't have Quidditch were stupid and didn't care about Quidditch so that was actually a very smart move not to include it, so all the money from that game just instantly went up in smoke as if you pointed at it with a wand and shouted "Confringo!"
So that leaves this show. Which they're already pissing off the contrarians who got into HP so they could support the Death Eaters, because they're also the type of people who would be pissed off by the Snape casting, and we've only gotten a few casting announcements so I'm sure he won't be the only one. So they're between a rock and a hard place now, if you support the show, people you don't like will benefit, if you don't support it, other people you don't like will benefit.
Mind you the show itself might be good. Assuming they do one book a season at most, maybe two since the early ones are shorter, I figure what will end up happening is we'll get another adaptation of Sorcerer's Stone and then the show will get canceled and we won't get any more. But that's cool with me because that one was always one of my favorites, very short and self-contained, comfy and whimsical before the plot started getting all dark and dreary. So even if all we get is another kino adaptation of book 1 I'll be very happy indeed.