I'm not a fatalist, I'm just pointing out a fact. FOSS is far from winning.
FOSS has barely "won" the lower levels of the stack and the highly technical niches. But the more you move towards user-facing applications, the more proprietary things become.
You've just proved his point more than you ever wanted.
> checking email
On the (probably) proprietary Mail or Gmail app.
> waiting in line
On the (probably) proprietary app for whichever thing you're staying in line for.
> playing Angry Birds
...
> making a photograph
...
> or checking up on Facebook
...!
Who care if the kernel, heavily modified and buried 100 layers deep is Open Source if all the apps users actually use are proprietary?