I was one of the close voters, and I looked at the FAQ before I did vote. I will try to recap the things I considered before voting and rationalise my, partly intuitive, handling.
I read the 5th bullet item as that a package does not have to be exclusively *nix. Of course Skype falls in that category.
I felt there was nothing in the question that made a particular link to *nix apart from the irrelevant—for the problem—Ubuntu tag. I found the question more appropriate for SU (or for that matter on AU), unfortunately that is not (yet) an option to recommend when marking off topic on unix-SX, otherwise I would have done so.
I realise that more appropriate might not be a good motivation for closing a question as off topic. What probably influenced my decision is that it was a first question (rep 1) and I think the OP should be redirected to a (IMHO) a more appropriate site.
This is a grey area, and because of that I am happy we need multiple votes to close a question, if it had not been closed, I would have taken notice and change my behaviour in the future (it would be nice to get a notice automatically on what happened to a question one voted upon, or at least when the outcome was different from ones own vote).
I feel I should go with my non-*nix-specific questions for Firefox, Musicbrainz Picard, VirtualBox, Chromium, Calibre, LibreOffice and Acrobat Reader (to name a few applications I use on Ubuntu) to SU. If questions about those applications show up here too much, without any relevance to *nix apart from the OP running *nix as her/his OS, this site will not be interesting to me. That of course would automatically solve the problem of one of the close voters for these kind of questions hanging around here :-).
This answer by Michael graphically closely represents my opinion on this.