Survival of fittest would be if opinions were allowed, and let the best one wi

Not at all. By definition, the only thing a survivor needs to accomplish is to survive.

And who decides which one is "the best"? You need someone to make that judgement. That was exactly my point. You may not agree with a typical moderator's judgement, but that doesn't change the fact that, within that narrow context, they are playing the role of deciding what is good.