"Frankly I do not see any other significant business innovation coming."
You have a severe lack of imagination. Consider that while there will be N business innovations in all, there will only be one that will be the last. So I'd say it's more likely there will be many more than no more.
It's bad form to ask him to defend his point when you're defending your own by reiteration. Why won't innovation in such a magnitude 'happen again anytime soon'?
Because disruptive, game-changing, mind-flipping innovations take years to be accepted. Only a few individuals will understand the potential impact, the rest won't see it or understand it if they witnessed it.
So maybe that "next big thing" is already here. Maybe you saw it, read about it here or heard a couple of nerds talking about it, but chances are you would not care for it, or appreciate it because you would not know it.
The next big thing is the unknown unknown and it takes years for people to comprehend it.
You have a severe lack of imagination. Consider that while there will be N business innovations in all, there will only be one that will be the last. So I'd say it's more likely there will be many more than no more.