"all the early adopters"? Isn't that's a bit hyperbolic? Can you clarify this?
Not an uncommon view. There are people who believe that no competent developer uses Windows machines for development, for example
What does MS-only mean ? They actually provide client apps for macs, if that's what you meant.
By MS-only, I refer to Microsoft technologies and development tools for Windows, Windows Phone, Azure. Early adopters (alpha geeks, developers, etc) generally use Macbooks now which you can see for yourself at any tech conference. Microsoft really doesn't market to this group, it pretends they don't exist.