Usually, historical figures in Jinyong's works are characters which match their roles in history. Some exceptions are made for characters whose feats were displaced by the protagonists (e.g. Lv Wenhuan, Zhu Yuanzhang), but I want to focus on Wang Chongyang.
In Taoism, Wang Chongyang is an important figure - he was the one that introduced the concepts of Buddhist style monkhood (chastity, meditation etc.) into the Taoist priesthood, eschewing traditional practices such as Chinese-style alchemy, exorcisms and talismans etc. In SDYXZ and SDXL, he plays a similar role to Dugu Qiubai or Zhang Sanfeng - a super pugilist that acts as a treasure chest for the protagonist.
I, however, take issue to the way Jinyong has treated him. Despite being the No.1 of his time, his relationship to Lin Chaoying shows all the hallmarks of pettiness and spite. Why did he have to reject her advances in the first place? Opposing the Jin dynasty is all and good, but it does not require a vow of chastity - his letters and the Seven's words indicate a long-term relationship. Was he merely playing with her emotions?
When Lin Chaoying died, he had snuck in -using a route that he conveniently never told her about - to pay his respects and shat his pants when he saw Yunv Xinjing. The thing was, he held enough of a grudge to sneak back in once he got his hands on Jiuyin and used it to come up with a way to counter Yunv. The guy is such a sore loser that he has to have one up on the lady after she died!
Then there is the issue of Quanzhen: He did not pass down many of his most powerful techniques to his disciples. For instance, there is the issue of his ace card Xiantiangong: He was willing to teach it to Yideng but not any of the seven or Zhou Botong? Zhou mentioned that there were lots of goodies he never learnt because he lost his virginity - a few of the seven were virgins, why were they not taught any of these techniques? Again, Wang Chongyang is portrayed as a miser and a hoarder.
The worst is Jiuyin: He won the first Huashan Lunjian and claimed Jiuyin - to save others from it, or so he said. He forbade Zhou and the Seven to learn the martial arts contained within for this purpose. But then he goes and lets some fellow read it cover to cover as the result of losing a drinking contest! If only Ouyang Feng knew - all he had to do to lay his hands on Jiuying was to learn Qiu Chuji's technique of forcing alcohol out through his feet! Not only that, he goes and uses Jiuyin to fulfill a petty grudge against a deceased former lover/rival!
I think Jinyong does a disservice to Wang Chongwang by portraying him as he did in SDYXZ and SDXL. If we compare him to other historical figures who play similar roles (Zhang Sanfeng for instance), Wang Chongyang comes off as having serious character flaws, contrary to his practice of treating historical characters according to their roles in history. Not only that, but these flaws have been accentuated through the various revisions of his works (the third edition added the drinking contest bit, for one), as opposed to his trend of reducing the flaws of such characters and portraying them more positively!