At least for many parents, the 2DS has a few advantages over such products.
Given that, a more accurate description of the 2DS would be a "make-under" of the 3DS designed to hit the lower price point of $129. Introducing a lower-end product at a cheaper price rarely requires any justification beyond making the product more attractive to less-affluent consumers, which the 2DS will do even as it misses that "magic" $99 price point. Nintendo did offer a further justification, though, bringing the starting point of the product's recommended age range down a year or two. As a result, the product's form factor -- a thin wedge -- sacrifices some portability for ease of access and durability (even though the screens are now exposed, as with modern smartphones and tablets).
The stronger resemblance to those slabs may have competitive undertones. Nintendo has exhibited a Disney-like capability to keep its character stable fresh. However, a glut of inexpensive Android tablets such as the ASUS MeMO Pad HD 7 and Hisense Sero 7 Pro, as well as the more educationally high-minded (and bilingual) OLPC XO Tablet, stand to cut off kids' early exposure to Nintendo's franchises. Other competitors that are tempting weary parents include hand-me-down or borrowed smartphones. Regardless of screen size or operating system, though, you won't find Nintendo games on these devices, and so it's imperative for Nintendo to get a device in front of kids to establish recognition in the company's native medium. No amount of merchandise or cartoons can really substitute for that.
The 2DS is a chip off the old (hinged) block.
At least for many parents, the 2DS has a few advantages over such products. There's no (explicit) advertising and little risk of stalking or access to inappropriate materials. Without 3D, though, the 2DS must rely on a different sort of depth in its gameplay to ultimately win over parents. That may be a hard sell when a free copy of Candy Crush Saga is a click away.
A longtime supporter of 3D, styli, resistive screens and dual screens, Nintendo hasn't just made odd combinations of technologies work; it has also made the hand-held gaming market itself work. The 2DS is a chip off the old (hinged) block. It will help keep Nintendo's world exposed to younger consumers, but will struggle to distract consumer attention from cheap and powerful convergent devices in the larger, budget-conscious mobile gaming market.
Ross Rubin is principal analyst at Reticle Research, a research and advisory firm focusing on consumer technology adoption. He shares commentary at Techspressive and on Twitter at @rossrubin.