superchunk on 16 June 2016
Its not a matter of hardware support but support of the OS.
Consoles are moving to a mobile-style platform where every couple years there is a hardware iteration and separately there are OS and middle-ware tool iterations. Hardware only becomes obsolete as the OS/Middle-ware can no longer support it, again similar to any phone which is actually about 3 or 4 years out.
Meaning in 4 years XboxOne / PS4 won't receive latest OS updates, but may still play games as long as those games will run on that version of software. This is why you're seeing more powerful hardware only a couple years into their lives.
