If anything is on their way down to hell, it's portable gaming devices. 3DS had multiple new minor features, which really could've been in previous DS version, but 3D was its only big one.
Besides the totally new guts, you mean. How about you compare Mario Kart DS with MK7?
Many people with a 3DS don't even use the 3D, they only play the 3DS to play the new games which only release on it.
I would suspect that many more do use the 3D, and I for one actually benefit from it's use. Kid Icarus is much easier (but still hard) if you don't have to think about how far off the bad guys are. And really, if you're not buying a system for it's games... why are you buying it?
PS Vita was a step up on the PSP, but again, it has many features which should've been there from the start. It has fun new games, but they could also have run on the PSP just fine.
Sony didn't know touch screens were going to be such a good thing 8 years ago... There's no reason that "should have been there from the start". And the back panel is a totally new thing. I guess by many features you're talking mostly about the second analog?
Increasing the resolution, revamping the graphics, and adding new inputs aren't things you can just
do for handhelds. That falls to the master race. Making major changes with every revision would likely screw everyone over due to cost and platform fragmentation.
I also wish my parents and other relatives would stop playing Angry Birds or Draw Something on their iPhones and calling themselves "Gamers". Phones are a stupid way to game, but somehow increasing in popularity.
Of course, this one thousand times over, haha. Phones are getting better with their games though. Slowly.
Wouldn't it be interesting if Square Enix's mobile games ended the Game Boy brand? I hope that doesn't happen, but it's not totally impossible.