I put the term "whistleblower" in quotes because I think it has been the wrong term right from the beginning.

I also don't think that "simple case of altruism" ever describes whistleblowing. To do something that will likely cost your job at least, and see you incarcerated at worst, requires a level of conviction about certain things that most people do not share. Even the whistleblowers that almost nobody questions any more (e.g. Daniel Ellsberg of the Pentagon Papers) had viewpoints that most people would have said "tainted" their behavior beyond mere altruism. They wanted the world to be different.