Sure there is a lot of knowledge work associated with what you mentioned, and with most products out there. But there is a many-orders-of-magnitude difference between the manual labor aspect and the IP aspect of bringing a product to market.
(I know I'm taking a leap here, but) I believe this scale difference is a necessary part of the equation. There has been a growth in knowledge based jobs precisely because of growth in population plus growth in productivity in the output of manual labor jobs. In a world where production costs are near zero because its fully automated, there is still the built-in costs of the materials themselves. This puts a cap at how cheap a product can become. Unfortunately, 60% of the population now has no money to speak of so even a fully "optimized" price is too much. There will potentially be many dirt cheap products but not nearly enough customers to buy them.
As I'm sure any discussion involving economics would :) I've given it a good think and I find it hard to come up with something concrete.
In our current economy there is still the driving force of profit that creates jobs. All jobs that don't directly support the necessities of life, are either directly selling products to consumers or supporting companies directly selling products to consumers. There still has to be a mass of people to sell crap to for the economy to function. Under the assumption that all manual labor, factory and most service level jobs are gone, there is only a small market for non-essential products, which effectively puts a cap on the number of knowledge workers.
Browsing through the new section on HN I came across this: http://www.slate.com/id/2287531/. It seems to support my contention that technology itself does not cause economic growth.
(I know I'm taking a leap here, but) I believe this scale difference is a necessary part of the equation. There has been a growth in knowledge based jobs precisely because of growth in population plus growth in productivity in the output of manual labor jobs. In a world where production costs are near zero because its fully automated, there is still the built-in costs of the materials themselves. This puts a cap at how cheap a product can become. Unfortunately, 60% of the population now has no money to speak of so even a fully "optimized" price is too much. There will potentially be many dirt cheap products but not nearly enough customers to buy them.