If Hogwarts' dress code was a little more lenient…requiring the gray skirt, white shirt, House robes & tie, but allowing you to do anything else with it. I'm a Ravenclaw, but my fashion choices for each House. Made by little ol' me o I have to agree!
I feel like he's saying, "I'm getting too old for this stuff. I've killed Voldemort and, not to mention, escaped him about a bazillion times before that and I've saved your sorry butts since we were eleven and this is how you repay me?