Every point he makes is absolutely correct, and I think comparing them to computers as a rising technology is apples to oranges. For one computers made most of its improvements exponentially because the number of transistors doubled every 18 months. 3D printers don't have an equivalent part, like the transistor, that just simply scaling up makes things perform better. The things holding back are outlined in his article: limited choice of materials, lower quality of the part, slow print times, high cost for mass producing, inability to mass produce, etc. All of this will improve with time, but it won't be on the same time scale as computers.

Now there are somethings I don't think he discussed that change manufacturing because it requires imagining a different way of working. These are the more transformative changes that might have no previous equivalent to compare them to.

For example, the ability to have a de-centralized, agile work force. My wife worked for a company where the M.E. were in the states, but software teams were in Europe. They were constantly sending manufactured parts with people as they physically traveled between offices. It was far cheaper to do this than ship the boards and cases of manufactured products to the team. However, with a 3D printer they could email the CAD drawing to the other office and in a day they could print it out. This is a big change in how fast things could be turned around, and save $1000's of dollars, allowing them to iterate faster.

Another change is 3D printing molds for doing injection molding. Some rapid prototyping shops already do this today. Creating the molds is time consuming, but 3D printing gives you faster turn around. And also more complex molds. This plays to 3D printings strengths low cost for low volume one offs. The quality of the part could be a problem, but hopefully that will improve with time.

I agree with what the author said, but I see the real limit right now is our own imagination for how 3D printers enable us to do new things we can't do now. This is where I see 3D printers are like computers as making something that was impossible before possible. These are much harder to predict. In a way it wasn't just computers that transformed us as much as the internet. Maybe there a companion technology that changes much of these assumptions made.

If we find a problem that 3D printers do better than anything else some of his assumptions could really change. For example, his assessment of 3D printers in homes right now is 100% accurate, but there might be some application we didn't see today for which 3D printers push into the home without significant changes to technology.