That is of course if there was no competition. Imagine if there had been no Sega Genesis or Turbo-16, Neo Geo or anything else at that time and Nintendo didn't feel the pressure of competing systems and thus didn't feel any need to put out the SNES. And if you can take that thought further, imagine they didn't have any competition in the future from Sony or Microsoft, etc. Do you think Nintendo may have just stuck with the very successful NES that had some classic games like the SMB series, Megaman, CastleVania, Contra, TMNT, Final Fantasy and many more.
Do you think eventually gamers would've gotten bored no matter how great the games because the graphics didn't change much after a while and at what point? When do you think they would've released a successor? Or would it have been possible we might still have been playing the NES if it somehow stayed successful.
Crazy thought, I know but I thought I'd just throw it out there.
I'll come up with something better eventually...