To the OP, I think your post describes the problem: Acapulco just isn't what it once was. It might be crime (real or perceived); it might be decision of the tourism industry there years ago to go more downmarket and "spring breaky"; it might be that Acapulco has been eclipsed by Puerto Vallarta, Cancun, and Los Cabos. The demand for flights isn't there like it used to be, and that's reflected in airlines cutting back service. You can still get there. It won't be as convenient as it was.