I think @roughly provided a good balance of practicality + optimism in their answer.
My thoughts: Not immediately, but yes, eventually. Humans have an innate willingness and desire to tinker+make things. Those qualities have gone into hibernation due to the vast array of mass-manufactured, off-the-shelf devices in the last decade. But many (have and will) come to realize that the satisfaction ceiling is so much higher when you build something yourself, getting your hands dirty, and looking at the product of your efforts.
Just that reason is enough to give rebirth to the experimental/inventive attitude that pervaded the 20th century. But there's also the fact that a personalized something can allow you to do stuff that a typical consumer product couldn't.
Pockit just aims to enable and accelerate the above realization for hardware, the way that libraries and frameworks have done for the programming world.
If you're asking aspirationally, I agree - I'd prefer a world in which this was what people expected and wanted from their technology. I think the ongoing success of Lego gives me some hope here for a mass market for tinkering.
If you're asking more practically - the success of Raspberry Pi, Arduino, Seeed, and others suggests there's at least potentially a market here sufficient to sustain a moderately sized business for long enough to be worthwhile.
Agree about the demo, too - there's some serious wizardry on display there. I think it's one of the projects that just gets more impressive the more time you've spent trying to do what they're showing off.
I find it hard to believe that one individual plus a small community of hackers have built all of it. Amazing, amazing work.
The one question I kept asking myself as I was watching the demo:
Is there a mass market for such a beautiful, elegant, modular computing device?