Steve Jobs and Apple, not Microsoft, killed the Linux desktop.
Think about it. If Apple had never recovered from their near-death experience, Linux would have had a Vista-sized window of opportunity to gain desktop share and interest from commercial software houses.
Also, there would have been no Android phones - they'd all be running a stripped-down Linux instead, since there would have already been a viable commercial software-for-profit ecosystem.
And there would be no App store with one company dominating a platform.