I had to scroll back up and see your name, check if my instructor was posting this, it sounds familiar
OP - let's carry your logic to the extreme. No boxer ever steps into the ring against a speed bag or jump rope, ditch 'em. It's a fight, not calisthenics, no sense in doing any burpees or running. Why hit a heavy bag, it doesn't even have arms. In favt, let's not practice ANYTHING other than the actual act we're attempting to improve - (if that is fighting) just fight.... every class, nothingelse is actually fighting except fighting right? I don't subscribe to that logic. I think there are several important aspect of training - partner drills (including chi sao), bag work, kata, weight training, cardio, stretching, etc.
Do I think one should be careful not to let the drill become the objective? Of course! Eliminate it? Definitely not.