Personal preference. I can respect two guys with poor technique and zero defense flailing away, but to me that doesn't make a great fight. Entertaining yes, but not top class. That's the same reason why Jung/Garcia 1 shouldn't be up there either. Give me Jung/Poirier - with less insane action, but 1000% more refined skill - over Jung/Garcia or Griffin/Bonnar any day.
Edgar/Maynard II had a crazy first round with Edgar showing a ton of heart to survive Gray's onslaught. He went on to display amazing recovery and composure to outclass Maynard for the next three rounds... And right when it looked like Edgar was going to win, when Maynard seemed to have no answers and could have packed it in and accepted the loss, he executed enough in the 5th round to steal a draw. There wasn't as much damage dealt, but the fight was far more dramatic, tense and exciting. Even when Edgar was cruising, there was always the threat that one big Maynard punch could trigger a repeat of round one. But to Edgar's credit, he learned from the first round and showed excellent movement to outstrike Maynard without getting hit himself, and even got the better of the wrestling despite being ~15 pounds lighter. It was a brilliant turnaround.
For me, Griffin/Bonnar is the "Transformers" to Edgar/Maynard II's "Jaws".