And how is betting of people hitting each other being considered as legal and ethical in today´s world?
It's much better than countries going to war and in conflict, boxing is considered art in sports and Olympics you need to be physically fit and well trained to compete, they are trained to get hurt and hurt they are not average people they undergo training and they are certified to go on competition, and boxing is well regulated so they are not fighting to the death.
Boxers are not only thought how to beat the opponent, but they are also thought how to protect themselves at all times, and though it's normal that there are some boxers who suffers from serious injury, it's just rare compared to the total fights where boxers are still healthy after the fight.
So yes, there's no way it will be stop or ban as boxing is not the only sport that is considered a physical sport.