The statement that at some level species have been optimized is a religious belief, not a scientific one. Species are at the end of an evolutionary history that ended in the present. There is no reason to believe that that endpoint is optimal in any sense. It is certainly not globally optimal, and absent very strong selection, it may not even be locally optimal. Evolution explores an infinitesimal fraction of the possible states/pathways available. Without more thorough exploration and strong selection, there is no reason to believe things are optimal.

I think I’m not going out on a limb to say that no modern evolutionary biologist believes organisms are optimal. They simply survived.