I had a blast playing that game when I was a kid - as I recall it struck a good balance between simple, accessible controls while also being challenging (and without being frustrating). The gold cartridge rather than the typical NES cartridge probably also lent it an air of specialness.
As I got older I realized that most kids with Nintendos had more games and I felt left out for never having played Zelda or Metroid. But man, Micro Machines, Super Mario Bros 3 and Faxanadu was all I needed.
It was such a great game - very simple to just sit down and play, and lots of fun. Sure, there were no powerups, vehicle customizations, no track designer, but it had amazing track/level design. Who as a kid didn't race their boats in the bathtub, cars in the kitchen...
As I got older I realized that most kids with Nintendos had more games and I felt left out for never having played Zelda or Metroid. But man, Micro Machines, Super Mario Bros 3 and Faxanadu was all I needed.