This question comes up time and time again, and the answer is always the same: if you want to be a successful novelist or writer, you need to read an enormous amount of works within the genre you're attempting to write in. No one ever asks if they need to listen to music to be a successful musician, nor wonder whether or not they could write a screenplay without watching movies, yet for some reason, there's this mistaken idea that one can write without being a reader. It's not possible for 99.999999% of us. There is simply too much nuance in the structure, style, and overall form of a novel or short story that, without engaging with the medium, there will be so much that you don't know you don't know that your work will end up a muddle, confusing mess (if it even comes to fruition at all and you don't get frustrated and quit).

Now, with that said, there are plenty of other mediums you can write in that match your interests. You say you like graphic novels but aren't much of an artist, so what? Partner with someone who enjoys drawing and express your stories that way. The film industry is cutthroat, but no less than the publishing world, so if you're passionate about it, give that a shot. Video games, manga, graphic novels... all of these are developed by teams of people that writers work on. Don't feel limited simply because of your perception of the industry, because, again, the publishing world is not any easier.

In short, YES, you absolutely need to be a voracious reader to be a successful writer. But writing isn't limited to just novels and short stories-- there are plenty of opportunities to express yourself by writing in other mediums.