This was my thought as well! Even after the menu refers to Ralsei as "they", Flowery uses "he/him" all the way until the end. As someone who is gender fluid myself, there is like zero representation out there so it would be cool.
A lot of it was purely because the HP books used the word "Witchcraft". The Narnia stories are filled with Christian allegory (anyone who denies that is just being silly. CS Lewis wrote tons of religious stuff and was a Christian) and the ice witch was evil, so the religious people liked that.