Is there any example of "change the system from within" having ever worked? I can't bring one to mind off the top of my head, but that doesn't necessarily mean much.
Well, I'm not familiar with many examples relating to corporations either way, but I think legislation is a great example. There have been countless instances of citizens starting successful political movements within their own countries, but I'm not aware of any laws that were changed as a result of people giving up on the US and moving to Canada, for example.
It's definitely frustrating when advocates of this argument are those that benefit from the subject exerting effort keeping the system in-place. I feel it's an overreaction to broadly generalize "change the system from within" arguments to this extent though.
I didn't make a generalization. I asked a question.