I actually don't disagree with your general point, but the idea (and the fact that your fist thought was) that the rangers will turn around and start poaching rhinos themselves seems like a really odd argument to be making if your aim is the capitalists who create and uphold the industry in the first place.
E: like, you focusing on the rangers is exactly the same as other people focusing on the poachers - neither are in charge and both are there making money for people who would never get their hands dirty.