The data doesn't show that people aren't buying Windows8. It shows that people aren't buying PCs. It's not hard to buy a laptop with Windows7 on it either - so suggesting that the decline is "because Windows8 is turning people away" seems to be cherry picking the data somewhat.
Mega-plummet around the time W8 got released. And no, it's not particularly easy buying W7 PCs, except for businesssy computers (where you often need to request W7 to have it installed), they are all pre-installed with W8.
"At this point, unfortunately, it seems clear that the Windows 8 launch not only failed to provide a positive boost to the PC market, but appears to have slowed the market," said Bob O'Donnell, IDC Program Vice President, Clients and Displays. "While some consumers appreciate the new form factors and touch capabilities of Windows 8, the radical changes to the UI, removal of the familiar Start button, and the costs associated with touch have made PCs a less attractive alternative to dedicated tablets and other competitive devices. Microsoft will have to make some very tough decisions moving forward if it wants to help reinvigorate the PC market."
Such a crash RIGHT AROUND THE TIME OF THE W8 RELEASE has nothing to do you W8? Keep telling yourself that. The decline on W8 premiere is far harder hitting than the usual PC decline visible since a few years.
Maybe all the "trolls" had a point, huh? There was not exactly a shortage of War & Peace long posts deriding this thing all over the net. And not in the usual Linux or Apple circles, but often by Windows devs and admins. And contrary to what you might hope or think - the amount of outrage in THAT group was unprecedented this time around.
And no, these were not whining. On this very forum you weren't able to counter most points effectively yourself, but developed a habit to squelch discussions with "tl;dr" instead. All over the net the arguments against W8 were overall much stronger than the ones for it.
Oh and what about the "60 Million licenses in the first months" number Microsoft touted? Somehow neither the sales data provided by the market analysts nor the OS statistics on Netapplications jives with that. It was probably just like I said here before: Most of those W8 PCs were (are?) still at the shops when the number was published.