If you step outside of the startup bubble, you'll find that the bulk of .NET stuff is boring line-of-business apps developed by large corporations using the MS stack from top to bottom because MS is "safer" than open source.
I actually work at a .NET startup doing non-traditional things with .NET and we have the hardest time hiring new developers because of the "enterprisey" nature of .NET and the type of developer that generates.
Enterprisey is a matter of perception and shouldn't be a slur.