GBA could not run that game anyway. Amiga would never have moved to ARM either, they [Commodore] publicly dismissed this as a possibility.
And to be honest, that game with that level of track/vehicle detail is not even possible on a Playstation1, one of the most efficient custom 3D designs only. 3DO is not very good for polygons like that, just play Starblade(? Namco game) and you will see.
So what you have to ask yourself is....how long would it take for Commodore to be able to produce in a financially viable form a PPC machine as powerful as the £149.99 - £99 Sega Dreamcast? Say £499 is the cut-off point for a home computer without monitor.
Also there was the prototype Hombre chipset which Haynie proclaimed had better 3D potential than the Sega Saturn. This could have been exactly what the doctor ordered
Alternatively......maybe someone can tell us about the NatAmi 3D performance, there are some still shots but no videos of the screenshots shown on the website!