Sure, I'd be for this, personally.
But I doubt it would work on a larger level. It would fracture the user base (everyone with an older PS3 would not be able to play newer games with higher specs) which isn't something that the system with the smaller user base is in a position to do. Further, it would break the single, last standing chain that separates Consoles from PCs. Why did consoles rise in the first place? Because they were easier to use and set up, with no hassles like OS updates, HD upgrades, Other Hardware updates, and software installs. Just put the game in, and play.
Now, the PS3 has OS updates, HD upgrades, software installs, and with this change, other hardware updates, too. At which time, I"d have to ask: why aren't we just playing games on the PC again?