Short answer: No.

Long answer: No, I don't see them doing it. And even if they did, the degree of creativity that they have displayed in recent years makes me hesitant to believe that it would be any good. I very highly doubt that if they even managed to create some sort of throwback title, it wouldn't be as good as IX was anyway.

I know they've tried their hand and titles that were kind of throwbacks like Final Fantasy Dimensions and even stuff like Bravely Default. But in my opinion, they never manage to achieve the same standard of quality that their older games did back in the golden age.

So I'm pretty cynical to the idea of it.