I agree, but what do you mean "not precious about it?"
In that he's willing to make
big changes that make sense for the story as a TV show, and not to try and slavishly recreate the original story. Like, if he was sticking with the original structure of the novels, we'd have had 3 seasons of what would be, for the first two seasons at least, basically a re-enactment of Twilight in a fantasy setting. I don't that would have been survivable for the show. Indeed, even reading-wise, if I'd read Shadow & Bone first, I'd probably never have read any of the other books. Luckily someone told me about Six of Crows (I sadly forget who, now), and that's just an absolute banger.
The reason I note that particularly is that showrunners who are "fans" of the original material are often kind of precious about it, so you're lucky if you can get one who both loves the material and isn't precious.