No, not at all (imho), because if you're starting from scratch and don't even know which notes make up common chords or progressions, how in the world will you figure out how to compose something that sounds good / makes sense?

It's important to know the notes on the keyboard, but it's far more important to know how they work together in harmonious patterns. Composing entirely by ear is an option, but you still need to transliterate what your mind is hearing into notes on a page (preferably more complex than just a single note melody).

I 100% get where you're coming from, but I think a grounding in theory helps a ton with composition (even if you don't know how to play a specific instrument).