Despite the division floundering, A.J. still did have tons of respect, got the #givedivasachance ball rolling, and was the most recognizable female in the company. In short, she had a ton of respect in a division that gets little. Did she have much left to prove? Not really. And little to gain to go with it. By leaving after such a short time in the company, she'll likely be remembered much more fondly than she would have otherwise, as she's going out in her prime. Not only that, she had probably hit a ceiling in the company anyway, having already been champion, and with the WWE being a long ways away from having women main event a card, or even get more than a few minutes of screen time.