This is a lot closer to my thought as well. No one is saying extinction is beneficial. However, in the grand scheme of things, how critical was the unique Catfish that was only found in 1 river in Ohio? How many species have come and gone completely undetected?

Now that a species near the top of the food chain is missing, what species can grow and change to fill the gap? Isn't that evolution, you respond to a change in your environment.