I see comments but I don't see anyone debating it.
What exactly are you uncomfortable with - you don't think isometric RPGs are dying in the sense that a site like VGChartz would cover?
Isometric RPG are dying? Well VGChartz need wake up, since when it's new? The same goes for Shoot ‘Em Ups, Scrolling Beat ‘Em Ups, Mascot Platformer and “Classic” JRPGs.
All of them and many other genres have been killed by 3D. 3D brought two huge changes both linked to a graal of entertainment, immersion. Improved 3D cards allowed a better and better realism, and 3D allowed a player view much closer to the action (first person, over the shoulder and from behind).
That graal had been enough to kill ton of genres, but what weird with this article it's to fake it's new. It could seem newer because consoles had been a little late to jump fully into powerful 3D, but now even that is quite in the past, only the DS could have bring an illusion during some time but now it's been killed by mobiles, it becomes more obvious but there's nothing new, particularly with the PC point of view.
I don't think the evolution of the of last years of the big actors is about making more simple games not involving thinking, it's about not making games anymore but making entertainment. The problem with games is the dilution of interest when consumers grow older, it's not a problem with entertainment.
But I doubt it's that simple and I think that young kids and women disturb a lot their equations and I see only Nintendo with a real focus on this for the kids point of view but also with a huge worrying about what is happening with mobiles. And the casual market is also another data totally out of the understanding of the giants and I see only EA putting care on this.