Exactly. So as a scientist you cannot say that purpose is absent. But you did say it that it is absent. That was a philosophical statement, not a scientific statement. In the middle of your supposed scientific refutation of those who believe that purpose plays a role in natural phenomena, you said that it
does not. You did not say that you believe that it does not on a philosophical basis. You claimed science on your side. But you cannot do that from within science. You mix philosophy in with your science and don't even realize it. That's bad science and bad philosophy. Your opponents are much more aware of what they are doing. They don't claim that science and philosophy can be neatly separated but that even within science, scientists involve philosophical assumptions.
You can continue to insist that purpose is absent from the evolution of an eye. But your basis for insisting cannot be a scientific one.