Someone else would have filled the void. Sony wasn't so much "innovative" as they were in the right place at the right time... Past consoles had attempted to take their approach and it hadn't worked (was still too expensive) until it was clear the age of the optical drive/DVD player had arrived and Nintendo had cold feet (didn't hurt that they were more friendly with 3rd party developers either).
I see no reason why Microsoft wouldn't have eventually entered the fray, and I don't exactly follow how the Playstation was needed for "innovation"... If by some miracle Sega had survived into and through the dreamcast we were just fine, and Nintendo is always willing to experiment. Microsoft, meanwhile, either would have continued working with sega or filled the rest of the void left by Sony.
Really though, there's no way someone wouldn't have filled the void. Besides, while Video Gaming is more mainstream than ever and is worth more than ever (which I like), the consoles continue to become less and less unique as they charge towards the LCD (can hardly tell the Playstation and Xbox apart at this point). Still, while I myself am satisfied with the selection of games and where the industry is, the industry would have found its way forward without Sony.