Leonardo da Vinci, notable designer, and many other sophisticated people considered flapping wing aircraft. It’s easy to dismiss it as simplistic hundreds of years later once practical solutions already exist.
We in the artificial world do have our own local optima with quad copter drones. Flapping here would be more efficient. Consider seagulls that dive and change direction instantly, and can respond to gusts without missing a beat. We have nothing approaching that maneuverability. This is an active area of research.
Of course natural evolution has found only local minima in the fitness landscape, but as a designer it's been running its algorithm a lot longer than humans have. Its local minima may well be better than ours, and so worth trying to imitate.
This thread is so weird.