>I've read that you lose the meaning when watching a dubbed version but you lose even more with subtitles.

I dont agree with that at all. They are both translations and so will lose something, but a subtitle is not trying to match timing and mouth movement, so can change things to fit intent more.

>When watching dub you get to actually watch the movie

Half agree. some people have no issue reading subs out of the corner of their eye while keeping their main focus on the visuals. But to appeal to authority, Miyazaki preferred people watch dubbed (or at least watch the first time with dubbing) to focus more on visuals.

>how does sub improve the experience

For me, inflection. Language has a sound. The voice actors impart emotion and intention into the words, even if I cant understand the language. The timbre of a voice adds its own quality to a character that simply cant be replaced by a dubbed voice and actor in another language.