TBH I'm not a big anime/manga fan but the people I know who are into this stuff never even heard of it, or were put off for it being old and too text heavy. I'm sure at least some people here watched the movie, but the manga covers much more and is honestly one of the best stories I ever read; it touches up on a lot of subjects like politics, war, religion and philosophy. The overall tone is really dark too, and you can tell Miyazaki was loosing faith in humanity as he was writing it lol (he finished the manga in 12 years, from 1982 to 1994).