As you have noted, there are threads in which these healthy debates seem to be invited, but IMO, when they go off topic, they become a waste of FR's bandwidth.
It's kind of like another FR pet peeve of mine. Whenever a topic of the French is brought up, and Napoleon is mentioned as a French Emperor, someone always feels compelled to butt in with the fairly well-known fact that Napoleon was by birth a Corsican. It always makes the thread go off on a "was Napoleon French or Corsican?" tangent when that was not the object of the thread.
You stated it all so well that I fear I am not adding anything to you post, other than a "hear, hear!".
But.....
Napolean WAS a Corsican.
:>)