You do understand that, unlike most wild animals, humans change at a much faster rate, right?
The point isn't "humans did this (though admittedly I did throw a little jab in there)", the point is "drastically changing an environment can have devastating consequences".
Simply destroying something is the easy road. Because it means you don't have to think about what the problem is, only know that it's bad.
It's definitely harder to build something from nothing, but that's not the "solution" being offered. It's tomorrow's problem that you don't have to worry about yet.
It's not the easier solution, but it is the easier thought.