What is the reward for bumrushing a boss that kills you in one hit? None. You get sent to orbit or have to restart all over again. Either way. End-game content don't give the player options, THAT is the fundamental problem. You can't shotgun Valus down in a solar NF unless you're experimenting with triple titan bubbles. You can't fusion rifle Crota down either. There are no alternatives, there is only one option that yields the most effective way to obtain the rewards. That's why players camp. Not because of IB/BH. So there are 2 choices: All reward or all risk. Of course players will go for all reward.

Low k/d, no kills, no active engagement. Also if you sit back you risk letting down your team for lack of participation and support. The gun is fine as is. Let em camp. It's easily enough avoided.