Wildlife management is a direct consequence of environmental laws. Laws are created (normally) by Politicians. The majority of american politicians with any relevance in the last 100 years supported fire weapons, therefore hunting (because weapons were created to allow good citizens to hunt vermins and game. Aren't they?). I assume that for a politician in US, to reject weapons in public 50 years ago would have been social suicide.
Ecologists and biologists did what were allowed by the current laws to do, and what were hired to do. Not more, not less. There are around 22 american people trying to save the last 15 american vaquitas or so. Their ships are shooted and harassed rutinely for removing illegal nets.
When the animal will go extinct in a few years, we all will see how some people still blame on they. I'm 100% sure of that.
Sounds like maybe said ecologists and biologist were part of the original problem?