I've tend to notice that with books like lord of the rings, game of thrones and Harry potter. Comics people are ethier more aware of the movies or cartoons depending on the era they grew up in and get suprised when the adaptions of comics are a mix of different stories rather than a full on adaption, though comics continuity would make it more impossible to ever full adapt stories unless their are elseworld stories. Though games have started to become as big of a medium.Who? Are we suppose to know which dragon quest character you are referring to by instinct?
The anime had a lot of filler promoting Hinata because the staff was obsessed with her. It is why they ended Naruto marrying Hinata because that was their end goal all along. Without the anime, Hinata is a character that's barely involved in the story and barely interacts with Naruto despite professing love for him. With it, while she still isn't involved in the story that often, she is constantly by Naruto side, and constantly thinking about how much she loves him.
Most Western fans seem to hate reading anything, and prefer just to watch a tv/movie/anime and accept that as canon. I lost count of the people I have met that say they love an adaptation, that they love as well as care so much about the story, that they wish to learn more about it, but will never read the source material. Saying excuses like they want to watch all the show first before they read the book, so they won't get spoiled. Then they never read the book. Even if they do, they hold the adaptation over the source material, and will differ to that when inconsistencies happen.
My guess is because they are more accessible to watch and consume, especially with streaming services in recent years. Another reason which came from a youtuber called lily orchards who did a video on making fun of J.k.rowling, during which mentioned that due to the education system making reading more like a chore for kids, becoming less fun making it into assignments of highly revied books by adults. With some only getting back into reading when a fun book at the time like Harry potter came along.
So I wouldn't be suprised if many of the anime only watchers would view the 700 hundred chapters chore to read, even though the anime became worse than that due to filler.