One theme the Netflix version of “The Witcher” stresses is a magic wielder’s ability to correct anything and everything that they don’t like about their appearance. All the sorceresses that graduate become more beautiful than they ever were before. Yennefer in particular goes through an extremely traumatic process of correcting her hunchback.
And while Yennefer did have a corrected hunchback in the Andrzej Sapowski books, the results were different. The books indicate that mages can correct physical flaws, but only to a certain degree. In fact, the books describe the women of the order to only be “pseudo-pretty.” The magic corrects all major flaws, but cannot fix everything.
In the novella “The Last Wish,” Geralt describes Yennefer as attractive in some way but “not a great beauty.” While magic corrected her hunchback, she still shows evidence of her past deformity. One of her shoulders is described as being higher than the other. So while what is considered a major physical flaw in the books is largely corrected, it is not perfect. This is a different picture than the show portrays.