Extremely stable products do exist. The Z80 wouldn't still be made (after almost 50 years) unless software needs that CPU, and at this point that has to mean st

Extremely stable products do exist. The Z80 wouldn't still be made (after almost 50 years) unless software needs that CPU, and at this point that has to mean stable software, right? But in this case, the software works as it did, provided that you give it the surroundings for which it was made. The change needed isn't one of the four classes you point out, but rather a fifth: - support for new networking technology For the N95, a new web stack, presumably including xhr, webrtc and the other goodies so many apps use nowadays. For the Playstation, the ability to connect to new WLANs. I suspect that new hardware would be needed in both of these cases. Running webrtc on a CPU from 2007 sounds dubious, and didn't 802.11foo change something extremely low-level wrt. hardware?