I actually bought Asterix & Obelix XXL a few years later for my GBA SP.
I found the graphics to be pretty nice. (though if you look harder, you can see they are merely using 2D sprites in a 3D environment).
However, the game was pretty repetitive. (and also pretty hard later on)
Plenty of other 3D games got cancelled as well : Dune Ornithoper Assault, Shi'en GBA racer, GP Advance (very impressive!)...
Shame that most of these games for the GBA turned out to be cancelled though.