Problem with 3d printing (and one blemish on this otherwise fantastic essay) is that 3d printing related stuff I think is too sexy to be a good startup idea. Much like video games or developer tools, it's too meta and every nerd on the Earth who has read any sci-fi would jump at the chance to work on these types of problems.
That's not to say that being an employee of a company working on these wouldn't be a lot of fun, if that's your thing. But founding a company around sexy technology is more about self-indulgence than trying to create a wealth generating enterprise.
I worked on what I, at the time, called software to do "3D printing" in the late 1990s. CAM - Computer Assisted Machining - software. (It was CNC drilling, not additive sintering).
Sure, it was very expensive (like a mainframe), not cheap (like a PC). However, it definitely wasn't sexy. Nobody, not even sci-fi nerds, was jumping to work on that type of problem.
It's actually quite schlepy, at least the part we did. Lots of maths and problems with floating point rounding errors, and weird edge cases of strange shapes.
Bet there are plenty of schlepy bits in the new, cheap world of 3D printing. We're certainly early enough, it has nowhere near even begun to play out.
That's not to say that being an employee of a company working on these wouldn't be a lot of fun, if that's your thing. But founding a company around sexy technology is more about self-indulgence than trying to create a wealth generating enterprise.