Once again injuries in other sports or not done to the head, and the brain being one of the few parts in the body with no nerve endings doesn't feel anything, so a boxer is less likely to know they have brain trauma, then a basketball player knows they have a sprained ankle or bad knees.
As for the example of the rubber around the elevator, of course it would lesson the blow if you had the rubber around hte elevator, the potential energy convert into kinetic energy due to gravity as the elevator goes down, with the rubber around the outside a lot of that kinetic energy is absorbed into the elastic energy of the rubber.
Its like dropping an egg in a box onto a foam mat, or onto hard ground. When its dropped onto hard ground, there is nothing else that absorbs the blow, and the egg breaks, but when you drop on the foam, even though the egg is moving independently of the box, it is far less likely to break because of the absorbtion of the foam that neutralizes the normal force that is otherwise placed on the egg by the floor.
Another example is a car, the cars nowadays crumple more easily than cars back in the day, and wearing a helmet and using sparring gloves is like using a modern day car, the glove has extra padding which acts like rubber and absorbs part of the power, and the helmet isn't made of metal, it absorbs part of the blow, if this weren't so people would go down as often as they do in a pro fight, but they don't because the head trauma is lessened. You can argue that won't help them in the long run, but per punch its much less damage being done to the head.
There is also the nature of amateur boxing which is more like point sparring in that boxers only need to land cleanly on their opponent opposed to landing hard. Most boxers in the amateurs if not all boxers tend to not follow through as much in an amateur fight because they would rather get their hands back into defensive position to avoid being counter punched more so than in the pros. Also as soon as a fighter looks hurt in the amateurs usually a standing 8 count is called whereas in boxing they will allow you to get hit the point you go down or you can't defend yourself. This is the main argument why MMA is safer for you because, your either stopped or your in good enough shape to continue, only in boxing are you allowed to recover and keep going, its then that you do the most damage to your brain.
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