For me, backwards compatibility was one of the biggest selling points of the 60GB PlayStation 3. It really was.
But I've learned something over the course of this generation, and I've concluded that I really don't care if the next PlayStation has the same feature. I know, I have to explain, as most say b/c in the PS4 is incredibly important to them (and that's perfectly understandable).
Thing is, I've realized why I keep the PS2 hooked up. My current PS3 slim model doesn't play PS2 games and in truth, I don't like the way it emulates the PS1 titles (sound keeps cutting out in Castlevania: Symphony of the Night , damnit). I use my PS2 to play any and all PS2/PS1 games I feel like revisiting. And in looking at my PS3 collection the other day, something struck me: I really have no desire to play anything there again, with the lone exception of Heavy Rain .
It has absolutely nothing to do with quality. I think we can all agree that games like Uncharted 2: Among Thieves , Uncharted 3: Drake's Deception , God of War III , Metal Gear Solid 4: Guns of the Patriots , The Resistance and Killzone titles, and Gran Turismo 5 are all pretty great games. And right now, every single one is well worth playing at any time of day. But I've discovered the reason I go back and play the older games is surprisingly simple, and those who remember those titles will sympathize.
It's a two-part combination; equal parts nostalgia and a style of gameplay we don't have much anymore . When I go back to Final Fantasy VII , it's not only because I want to relive those glory days, it's also because consoles really don't have epic turn-based RPGs with world maps, now do they? That goes for a lot of my RPGs. And sure, you could say Grand Theft Auto: Vice City is all about nostalgia, but I think we all know that GTAIV went in a different direction in terms of gameplay style and atmosphere, and GTAV will likely be similar. That arcade-y crazy theme in VC? …may not see that again, and you'll never see the 80s theme again, either.
We're not really redefining gameplay anymore, so with only a few exceptions, I can't see going back to the PS3 games in the future. Why? Why would I play Uncharted 3 when I have Uncharted 4 ? Or Gran Turismo 5 when I have Gran Turismo 6 ? Or God of War III when I have God of War IV ? All the new versions of those games will be pretty similar gameplay-wise, and likely better in terms of technical advancement. I go back to old PS1 (some PS2) and SNES games because I just don't have that particular style of entertainment anymore.
Chances are, most any PS3 game I look back on will be under the shadow of what may be its superior PS4 counterpart. It's most of the reason I'm not going back to play many games at all this generation. The bottom line is that I only really want to have access to gameplay styles that have died out (or are dying out), and while you find that two generations back, I don't think any gameplay styles we see in the PS3 generation will "die out" when the PS4 comes around. At least, I don't think so.