Sorry, looks like we'll have to agree to disagree. Not sure if you were around then, but Xenix (Microsoft's version of Unix) already existed as a real product several years at that time; I actually did a SW development project using it in early 1984, and remember it well.
What happened, and gave rise to Esther Dyson's famous article, was that Microsoft decided to stop further support & development, but didn't communicate it. It wasn't a marketing ploy, because this was a programming tool, not consumer software, and at the time Microsoft didn't really do active marketing to that segment. The original article is
here, where Dyson defines it as "good ideas incompletely implemented".
Sure, vaporware also includes cases where the product never existed in the first place and was fake, like the fraudulent demo of the Ovation office suite, but that usage was later.
Anyway, back to e-readers, while I hope you're right, I'm doubtful.
a specific issue with the panel used on the InkPad and Onyx i86 is one thing, but that wouldn't be relevant to the also-delayed Bookeen Ocean & TeXet (no mention of it since March) which use different panels; for that matter, neither would it explain the discontinued Pyrus Maxi or Icarus 8.