Hi, PN.
I don't think the area rule has gone out of fashion; because it's a fundamental law of nature. I think it has just joined the growing body of knowledge and technical capability that aircraft designers call on as they ply their craft.
The technical capability to use computers to fly an inherently unstable aircraft is a win-win outcome of basic physics; less weight, increased agility.
The key is, increasingly, the power to exploit fundamental properties of nature by using the enormous capacity we now have to process information.
Rgds SOS