There's a fallacy in the military that the highest priority is to bring everyone back alive and unharmed, but that's false. The chief priority is to accomplish whatever mission is set out for you, and with that in mind, to bring everyone back alive and unharmed to the greatest extent possible while meeting that objective. If the priority was protecting your people, you would never leave base/take off/leave port. The world out there is dangerous.
The first priority of the NHL is not to keep everyone safe, but to provide entertainment and make a dollar. Within that construct, the stewards of the game are motivated to promote a reasonable level of safety without sacrificing their main goal. Tweaking the rules and enforcement mechanisms in the service of improving injury metrics is laudable, but there are limits, because at the end of the day it's a bloodsport and a significant share of its appeal is the violence.
Hockey without violence is a very different animal, and you would lose a lot if you were to give up much of what gives hockey its unique character compared with other sports, namely the interchange of skill and grace with fearful violence. Threaten that core conceit, and you threaten your revenues. In any event, I don't think the stewards would support more than one day abolishing fighting, and even that point is a long way off in the future.