Got off light? A broken arm, his ear was hanging off, massive blood loss, lots of puncture wounds... light? You couldn't live through much more!

I would hope you could understand how putting the bear before the hunter would come across as anti-gun. A bear is a living renewable resource (much like an ear of corn), a person is a human life. You can draw an arbitrary line and label it "sentient" but it doesn't really mean anything.

As to the firearms recommendation there are way too many considerations to make blanket recommendations. A 12 gauge is lousy with most slugs and certainly with any and all shot. Only something like the big Brenneke hardcast slug is worth fielding in that platform. What you want is sectional density with a bullet of sufficient construction to penetrate adequately. Energy doesn't mean anything if you get no penetration. How people accomplish that is a maze of questions and compromises.

Bear spray cannot guarantee a stop, only a dead bear can accomplish that.