My complaint wasn't about lack of partner award availability, but that results were being filtered to only show AA flights. I had searched several originating cities with the same result. But the responses above got me thinking: maybe I'm misunderstanding how the webpage works. The "Filter By" was showing AA as the only option greyed out not because it was searching only AA flights, but because the results of the search came back with only AA options. So, the problem all along was simply lack of partner availability on the date I was searching, combined with me misinterpreting the design of the webpage. All is well now. I should have been able to figure this out on my own, but the above responses helped me see what was happening. Thanks.