I'd rather have them optional then mandatory (but preferably not at all). To make them mandatory doesn't serve much purpose. Back when they were, half the pilots just held them in their hand or wedged them in between their rollaboard handle, so cookie-cutter uniformity remained elusive. If they become mandatory, all that means is management will have to dispatch "hat police" to patrol for violations (of course, they could enlist a contingent of squealers). All that does is give them another tool to divide and conquer the pilots.

AA isn't a military institution, it's a civilian business. If we're going to convert it to the former, we might as well require reference to hats as "covers" and also might as well have morning formations, saluting, marching and a required PT regimen (don't complete it, you see the CP). A neat, clean business appearance is obtainable without a hat.