It boils down to who supports the console. In Nintendo's case, 3DS is being supported more than the VITA, thus it has outsold it in Software and Hardware several times over. Thus is the case for a console like 3DS vs. the PS4. Both have achieved astounding success but people will say PS4 is superior to 3DS even though quite frankly, I think this comparison (not directed to the OP but to the internet) is quite left field in general.
Handhelds and Consoles have a totally different premise...or else they'd be the same thing. Comparing Handhelds to Consoles is like comparing Laptops to Desktops. A Desktop is usually stationed at home or work and is capable of greater specs via upgrading. You can EASILY and MANUALLY install extra RAM, GPUs, CPUs, Mother Boards, etc. And that's because of the form factors of Desktops and the fact that they must be plugged into a power supply to do what they do.
Laptops, you're sacrificing power for portability. But the tradeoff is you can get what you need done on the go. Now I'm not saying that Laptops can't be as powerful as Desktops...it's just going to be a hella lot more expensive due to the chips, circuitry, and engineering needed to do so.
TECHNICALLY they are Superior. But that doesn't mean they should be looked down upon, nor have they in the past. Cough, I don't think I need to bring this up but DS outsold Nintendo's own Wii, PSP, Xbox 360, AND PS3. And currently 3DS is doing the same thing. Just because it's inferior doesn't mean they aren't as important as home consoles because people buy handheld hardware and software in droves. I only bring up sales to cement the fact that handhelds are indeed important.







