The display technology was tested for inclusion.
http://www.nintendoworldreport.com/news/24668
Satoru Iwata details the use of a special liquid crystal display to show 3D without the need for glasses in his latest Iwata Asks column. The technology was tested on the Game Boy Advance SP, but it was not developed as part of the console due to the low resolution of its screens at the time. Iwata tells the story:
"In order to make images look three-dimensional without special glasses, you display the images for the left and right eyes separately, and deliver each one separately. To do that you need high resolution and high-precision technology. We didn’t have that to a sufficient degree back then, so the stereoscopic effect wasn’t very sharp."
Nintendo has a rich history of 3D products, partly due to former Nintendo president Hiroshi Yamauchi's focus. For example, we already know that the Nintendo GameCube had circuitry built-in to support 3D display. A liquid crystal screen was developed to be attached to the GameCube, with a functioning 3D version of Luigi's Mansion prepared. The special liquid crystal for the display was too expensive, so the product was never released.
