Xbox and Playstation did the same thing with their old-gen consoles right before the new-gen consoles released.
In this case I find it a lot more reasonable since the Switch doesn't look like it'll have backwards compatibility unlike previous consoles like the Wii and 3DS.
People have been asking for a new-gen DS that can play the 3DS library, not have that stupid ass "3D" feature and have that clamshell hinge for better portability for quite some time now and seems like Nintendo intends to deliver on those features which is pretty cool.
My only gripe is that they chose now of all times to develop and release something like this. The 3DS didn't sell nearly as well as the original DS Lite due to a lot of totally redundant features like 3D. In the end people just want something they can play the new games on without having to buy some expensive as hell console with a bunch of features they will probably never use.
I've only recently purchased a 3DS from a friend for just 100 bucks so I can play the new Fire Emblem game and the Pokemon games which is pretty weird considering I paid like 75 bucks for my PS3 about 3 years ago. Refurbished 3DS go for around 200 some dollars still so you can image the consumer's problems with finding the right console at the right price. They don't want to buy the dumb looking 2DS that can't fold up but doesn't have that stupid 3D feature but they also don't want to drop 200+ dollars for a 3DS which can fold up but has that stupid 3D feature.