Is there any retro consoles that you never lived up to their potential? where the games fell short of the hardware?.
Personally I feel that the NDS was under-utilized, as it was a fully 3d capable console, that was used mostly for 2d pixel art games, and platformers. When it was able to support full 3d platformers and even a fan remake of portal.
Personally I think it would have done better against the PS2 in its later life, once the DVD craze died down. One of the reasons why the PS2 did so well was because it was a killer deal in the era of $1000 DVD players being the norm. But prices fell quick, and near the end of its life just about every home could afford a dedicated player.