As I sat there, seething and muttering under my breath, it came to me. I had a moment of clarity.
He didn't need to emphasize an improvement in quality, because it comes with quantity. The more you shoot, the better your images tend to get. You learn what works and what doesn't, and you figure things out that way. So, even though I was pissed, I'm not anymore. In fact, quite the opposite. I'm going to take what he said to heart and see if I can shoot more than I already do.
Also: I recognize my ego has been getting in the way a lot recently. I'm going to try and work on being more humble and trying to learn from the people around me instead of scoffing about how much I think they suck...
To all the people I've pissed off by coming across as a self-righteous, arrogant douche: I'm sorry and I'm working on it!