> you can not design us any better

I disagree, evolution is not perfect nor intelligent (as far as we know). It's never the "best design" that survives, it's always "good enough for now", merely better than other solutions at the time. A billion years of good enough is not necessarily the best it can be theoretically.

I'm sure we can find examples of living processes that are dumb and inefficient, with obvious room for improvement, but have survived for millenia simply because it was good enough.