Win8 doesn't deserve the bashing it gets.
Nor does it get the bashing it deserves.
The issue, really, is not that TIFKAM is a bad interface, but that it is a bad interface for desktops (or, at least, for desktops without touch screens ... but I suspect that if I had a touch screen I wouldn't want to use it much because my arms would get tired).
TIFKAM is quite well-suited to phones -- it's not IOS or Android, but it's a huge step forward from Microsoft's earlier phone OSes. It's also probably not bad on tablets -- in the same way that Android is -- because again the main interface is touch and the screen tends to be too small for the user to want to do two things at once.
What people are complaining about -- and quite rightly, in my book -- is the way that the "classic" desktop in Win8 has been all but sidelined in order to show off the new shiny ... functionality has been taken out of the desktop and added to TIFKAM, when it would have been better to leave the familiar desktop version alone and just added the TIFKAM version. If they'd been able to put ALL the functionality into TIFKAM and remove the desktop altogether the OS would have felt more cohesive and I think most people would have been happier to accpept it ... it's the fact that TIFKAM isn't finished enough to stand on its own so the rump of the desktop has been left in place like the wasted body of an old friend with a terminal illness that makes people uncomfortable with the new OS.
I think most people would be happier to live with the Win8 experience if the desktop had retained all the functionality it had in Win7, but with TIFKAM as an alternative ... or maybe as a desktop widget, or something.
It's the emasculation of the familiar desktop that really annoys people. Having an alternative GUI alongside it is peculiar, but not not a fatal flaw. Having key OS functionality that used to be available in the classic desktop now available only through TIFKAM is daft -- it should have been in both.
I daresay that what Microsoft hope eventually to do is to evolve TIFKAM to the point at which it can replace the classic desktop altogether ... but to do that they're going to have to think up some way of supporting multiple windowed applications running concurrently, because that is a very useful feature, and one that people are used to having.
What we have at present in Win8 is an OS that seems to fit nothing quite so well as a touch-enabled netbook, and (surprise) that's what they seem to be pushing it on with the greatest fervour. What they have now is no good for the desktop, though.
Microsoft keep coming back to this point. They produced generation after generation of PDA and mobile phone OSes that failed because they tried to bring the Windows desktop metaphor to the handheld, where it just doesn't fit. With WinPho 7 they finally did something different on the phone and gained a modicum of acceptance and it seemed that they had finally grokked the fact that handhelds and desktops are not alike, and deserve different GUIs. Thst doesn't seem to be the lesson they've taken away, though ... they're now trying to put a phone GUI onto the desktop, and that is ultimately doomed to fail for exactly the same reason putting a desktop GUI onto a phone did -- it's the wrong interface for the form factor.