Re: Home 3D printing...
...has only just about reached the level of the TRS-80. Up till now it's been more like the MK14/SCaMP level. The problem is the manufacturers can't see back to the beginnings of the home microcomputer age when "huge" sales initially meant, at most, a few 1000 units for dedicated hobbyists.
That's true in more than the size of the market but also the range of applications. A few weekends ago my fiance brought home a stereolithographic front panel bezel for a prototype something to do the surface finishing on. I saw it before he started work - no, the finish wasn't perfect but you could see it didn't need more than final finishing - the accuracy and fine definition were there already. It also felt nice and robust. He can't have disappeared into his workshop for more than half an hour for a light sand and spray paint. When he'd finished it could easily have been made using injection moulding and high quality moulding at that. Commercial application, commercial process (from a bureau service), commercial price tag and a very quality result. You can see the applications straight away.
Now look at the home 3D printers, producing unconvincing plastic blobs that look and feel as if they are about to fall apart at any moment. Where are the applications? Oh, I can see why a home user might want such a device but they don't fit the bill - they lack the structural characteristics for DIY, the model engineers or the self-described "makers" and they lack the precision and finish for the fine scale model makers or the artisans. That leaves you with plastic toys, and expensive and poor quality toys at that. When the novelty wears off what is the real use?
Your comparison to the home computer market is a good one but it goes further than you initially drew it. Yes, call it around the TRS-80, Spectrum, C64 or whatever. I don't see there being a linear successor to today's 3D printers just as there wasn't to those computers. Instead you had a story of divergence - the gamers went off to the Amiga and Atari and the "serious" home users went off to the likes of the Amstrad PCW. They only reconverged later on the PC, by which time you could say the technology was truly ready. I think 3D printing has to go through a similar story in the short term, supporting larger prototypes and acceptable strength on one hand and much better accuracy on the other. It's only when they come back together again that the technology is genuinely ready for the mass market.
Put that way it isn't something that is almost ready for prime time, we're at least two generations away. Businesses that do not appreciate that and plan accordingly are doomed to the same end as many of the firms behind those pioneering machines of the 80s.