No, it's not. Been following the "dream" since 1998. Then it was "a matter of 1-2 years" to "be ready for the desktop", nay, to conquer it.
Since then, the same three responses always come up:
1) "Well, I already use it for MY desktop, so there". Doesn't matter, you are an outlier. We're talking people at large here.
2) "Well, I installed it for my Dad and he goes along just fine". Sorry, a non-user with a friend to install Linux for him (and perhaps admin it) not representative of casual users.
3) Normal users are like "grannies" and "moms" (slightly sexist description which they use to mean: they do very little stuff with their PCs, like browse the web and check their email). Well, not really.
Some users are like that -- mainly older people. But most users are not, and as they spend more time with their PCs they become even less so. They would at some point want to: edit video from their compact camera, play a (specific, popular) game, create a presentation and share it, etc etc. As soon as they try a lot of those things, they find out that Linux doesn't cut it 100%.