Never heard that one before. I’d say the most likely outcome in the scenario you propose is the brake shoes (pads go with disc brakes, shoes go with drum brakes) would overheat and not provide sufficient stopping power.
If the brakes were applied hard enough to lock the wheels the tires would skid and the brake shoes would suffer no damage at all. Once you slam on the brakes the weight in the truck tries to move forward (momentum) and does not push down.
The weight will be transferred to the front brakes, which do most of the work anyway, but it might not be enough to prevent them from locking. Either way, the brake shoes will not be torn off their backing plates.
If you don’t overload the vehicle you really shouldn’t have anything to worry about, regardless of the brake type. Drum brakes are still used in lots of heavy-duty applications.