This is a dumb idea. The only people that need this type of processing power are large organizations who have enough resources to (a) buy a supercomputer or (b) use a distributed computing product that already exists.
That's patently untrue and the profile of the MacPro user easily demonstrates your contention is invalid.
The guy who most justifies the purchase of a MacPro is a person who is doing a lot of 3d work. That userbase could radically benefit from just such a model.
But you are completely missing my core point: Apple could instantly inspire a whole new class of consumer applications that utilize VR and AI like we've never seen it before.
In terms of VR We are talking something far more elegant and immersive than the clunky Google Earth.
As for AI, you could see computers involved in a host of new capacities :
A digital legal consultant
A digital therapist
A digital personal coach
Let's Face reality: A digital friend.
Look around and software development seems like it's peaked out. But In reality software development is still in diapers.
Latency issues are certainly limiting for some applications, but not all.
Consider: I can search the entire internet faster for keywords than I can search my local hard drive for a file.
And if Apple wanted to, and trade commission regulators didn't get in the way, they could easily build the mother of all networks.