I think you're asking "why Jaguar"?
It was simple industry consolidation. IBM (PowerPC) and all the other bespoke chip manufacturers were gone. AMD was the only company left that had GPU and CPU and was willing to build an APU. And the only CPU they had was Jaguar. It wasn't much more complicated than that.
If AMD didn't develop Zen, then consoles would either still be on Jaguar, or your consoles would be getting WAY more expensive.
You also have to remember (and I've said this before) there are a lot of headwinds for game consoles. In Gen7, consoles were not the largest consumers things like DVD drives, spinning hard drives, or memory. Now, they are basically the *only* consumers of spinning Hard Drives and DVD drives at scale. So costs are flat (or going up) on a lot of components, as well as Moore's Law slowing down.
I was thinking more from a marketing/product development angle (I'm a marketing/advertising guy, too!) and less of a technical angle, really, but thanks, hadn't considered the rising costs associated to the use of what is, essentially, "obsolete" and somewhat niche tech. As VX1 pointed out, there was a lot of "all-in-one" talk going on, trying to appeal to a broader range of consumers, I assume (always something desirable, but we know there are always compromises).
Price point definition, addressable market, additional revenue streams, projected revenue per console, all this stuff would've been affected by a more "bearish" market, so to speak, I assume? Was that a ever a significant concern, did it have any effect on what you guys were trying to achieve withe the Xbox One?