Star Fox was Nintendo's answer to the Sega CD and the various intermediate consoles between the 16 bit and 32/64 bit era (3DO and Jaguar).  Star Fox was an impressive game for its time, and though the framerate makes it mostly a nostalgia trip at the present, people still have strong feelings for it now.  The Super FX chip is used to present a 3D polygon gaming environment on the SNES so that people did not have to buy a new console for the latest tech.  Plus, who can forget the wanka-wanka-wanka voices of the characters.