Though I think the biggest problem there is that it didn't happen in a vacuum. It was one more event in a fairly long list of Microsoft technologies and APIs that were shipped to much fanfare, and then abandoned shortly after release. It made it hard to feel comfortable trying any Microsoft tech that wasn't at least a fewy years old. Including mobile APIs. Which, given what happened with Windows Phone 8, did not turn out to be an overabundance of caution.
The problem hurt more than Windows Phone, too. A lot of people got sick of having the rug repeatedly yanked out from under them, and started developing on non-Microsoft tech stacks. Which then removed a lot of the need to run Windows Server, and things sort of snowballed.
Despite all his infamous ranting about the importance of keeping developers happy early on, the Ballmer years turned out to be the era when Microsoft perfected the art of alienating developers.