It means, can we make less emotional/less intense/less personal .....comments? Can we 'cool it'.. is asking, 'Please, everyone, can we calm down a bit?' instead of 'on' , you could say, 'with' or 'in our approach to' Can we all calm down a bit before making/posting comments?

quit talking during the movie. cool it = stop commentary = talking about a movie while watching

"cool it" on here means "stop the comments", "Cool it " often means "stop it " John

I think that it's not making sense but if you heard it somewhere it will be : ( Can we call it on the commentary, please? )