Whether 90% of the Predator population are arseholes, whether Broken Tusk is considered an uptight fogey by Predator society, and whether all the other Predators in the book are different doesn't really matter.
I know that sounds silly, but that's how stories work. The Aliens in Aliens don't actually act like wholly mindless cannon fodder, either, but that's the perception so many people are left with, so that's what people make them. Perry gave us this noble, honourable Predator (or at least, fleshed him out) and he's the Predator character the reader connects with and sees through. It doesn't matter if all of the others are tools: Broken Tusk doesn't like them, so we don't like them. That's the popular image that comes out of reading the book.
Whether it's entirely accurate isn't particularly relevant. Broken Tusk is the "good" Predator, so all "good" Predators -- even the villainous ones -- ought to act like Broken Tusk.
That's how Perry made Predator honourable space samurai. It's the image that sticks.
(EDIT: I'm not actually saying I agree, I'm just explaining how it's entirely justified to say Perry changed the popular perception of the Predator).