If a passenger can’t lift the bag into the overhead themselves, perhaps they should check it either before security or at the gate.
Bad reactions all around, certainly. I can think of no quicker way to piss off a crew member with extensive safety and security training than to call them a “Waiter” when they’re the ones tasked with handling life threatening emergencies should they arise.
On the gripping hand, FAs are also trained in deescalation.