Have you ever looked at the output from a color printer from the 80s? Color dot matrix was absolutely hopeless for anything serious, and ink jet was expensive and not really that much better. Banding was the norm. Of course there were exotic and expensive technologies like dye-sublimation, but they were very expensive. If you are paying attention, that looks a lot like the 3D printing landscape now. The Makerbot style additave printers will probably go away, like dot matrix; and the photosensitave resin ones will improve dramatically and rapidly, like ink jet did in the 90s. They will come way down in price until they are under $100. Even the other exotic technologies will come down in price, like dye-sub did.
Off the top of my head I can think of a dozen or so occasions in the last year where a 3D printed household item or replacement part would have been useful. Remember, it's not just the cost of the part. if you can't 3D print then there is all your time spent sourcing and obtaining the part in question, if it's even available, and then hoping that it's suitable. The factors that will make 3D printing practical for household use are speed and cost. Print speed is exactly what is discussed in TFA. Cost will come down just like every other piece of computer technology ever.