It's more than a little expected nowadays: whenever new adaptation of an iconic or well-established character -- such as Geralt of Rivia in Netflix's The Witcher -- appears, a group of fans bombard it with negativity. Everyone has their own opinions on "toxic fandoms," but the general attitude seems to be that it's something filmmakers and artists are better off ignoring.
Actor Henry Cavill was asked about it an interview with Jake Hamilton. He was asked whether or not the witcher's world -- with all the hostility he's met with, despite his arguably noble intentions -- was at all comparable to toxic fandom. The actor said, "when it comes to fans, it is a fan's right to have whatever opinion they want to have, and people are going to be upset... I don't necessarily consider that toxic. I just consider that passion."
As Cavill later explained, the hostility of Geralt's world is rooted in bigotry, so it can't truly be compared to the occasional negativity vocally expressed by fans. The Man of Steel star is no stranger to the kind of fandom discussed in the interview, having appeared in several negatively received DCEU films over the decade. His view that that passion is not necessarily toxic, seems to be a view shared by The Witcher showrunner Lauren Hissrich, who interacts with the fanbase quite often and occasionally takes their views into account.
Although there were some complaints early on during production, the Witcher fanbase has been relatively accepting of everything it has been shown through trailers, photos and audio clips. That being said, it is entirely possibly that attitudes may change after release.
The Witcher stars Henry Cavill as Geralt of Rivia, Anya Chalotra as Yennefer of Vengerberg, Freya Allan as Ciri and Joey Batey as Jaskier. The series will be available to stream on Netflix starting December 20.