Since my shul is somewhat of a minyan factory, this is a daily occurence. I try to daven at the early minyonim, as the “shuklers” and “top-of-their-lung” people tend to daven a bit later.
But to tell someone to tone it down? No, that I wouldn’t do. They mean it sincerly, and the truth is, we really SHOULD be davening like we’re on fire, so I think you did the right thing by not saying anything