PS2 used a lot of the same chips in the PS1 for differing uses, so it may have been partial emulation, but I know that a large part of the "original" hardware was actually in the PS2. I don't think this is the case with PS3 tho, FWIW.
I won't argue semantics, so I'll stop after this, but I don't see downloading a game as backwards compatibility. It's just getting another game. To be backwards compatible, you'd be playing something that you already own and purchased, like those old cartridges you talk about. Then it's backwards compatible, otherwise, its just another product you can buy.. which is fine.. just don't pretend it's something its not.
And I'm not "complaining" about old games. I know full well that younger gamers never played most NES games... but ya know what... most of them aren't interested in them either. As much as you and I might love Super Metroid, try to get your average 12 year old to play it today.... you won't. There are exceptions, but I'm talking in generalities here.
I am *ABLE* ot play almost every game in existence on my PC right this very moment, and you won't see me saying my PC is backwards compatible with NES/SNES/GBA/N64/etc, so stop using that argument. I'd sound like a tool if I said that, just like I think Nintendo sounds foolish saying that downloading old games makes it backwards compatible.