However, the key feature of the butterfly is that it is meant to be tied in the middle, not necessarily the center, of a length of cordage/rope.

It would take a bowline on a bight to accomplish the same principle, i.e. two strands and the resulting knot is not near as tidy. So I don't think it is as practical or as useful, especially if you finished it of with an half hitch or overhand which is commonly used for the tail end of a bowline as an added safety measure.