This thread has been niggling at me ever time I see the title, so I suppose I'll add my two cents...

I think that whenever creativity is constrained by shoulds and conventions and ought-tos, it suffers, and so does the artist. Putting aside all of the technical reasons why it's good to learn open chords that others have discussed, how about that it expands your creative horizons beyond the tiny box of a particular genre? The great musicians and artists are the ones who are not defined by rules and conventions, and therefore sound unique and expand the art form.

You like the sound of open chords. That's more than enough reason to pursue and play them in pursuit of YOUR style and authentic sound.