For one, I think the marketing term is really used to explain Jin Yong's scope and impact, rather than a flat comparison of genre. In this sense, Jin Yong is, to Chinese literature, as impactful Tolkein is to Western literature.
It is a tradition within Chinese literature to prefer setting your work within our history. Romance of the Three Kingdoms is perhaps the most well-known in this vein. So to be critical of "creativity" here, is, I think a little bit short-sighted. It's like saying a Ken Burns documentary lacks the creativity of The Avengers, because magic powers and superheroes don't exist in the prior. Or trying to compare a book about the personal relationships of a cancer patient (I'm thinking "The Fault In Our Stars" specifically here) to the Harry Potter series. They are just fundamentally different things where creativity is executed in different ways. Who is to say that it is not equally powerful or creative to create characters that are deeply relatable, like Jin Yong's? In my opinion, his characters tended to ask morally difficult questions more often than Tolkein's.
Jin Yong wrote stories that were rooted in Chinese tradition, but his impact among young Chinese minds is greater than what even I can describe in a Hacker News comment. He wrote books that were about strength of self, moral character, freedom, and defiance in a time when the Chinese government strictly punished all of these things. I confess that I know nothing about Tolkein's backstory or history, but I can plainly see his impact. I think it is reasonable to say that Jin Yong's impact is as important and wide spread as Tolkein's.