The language itself is fine. Lots of good FP concepts. The mentality of the wider .NET community is close-minded and insular, lots of NIH syndrome, architecture astronauts and enterprise frameworks (even at small companies), which I think is borne mostly out of its corporate heritage. There are exceptions (the f# community for one, and the odd nuget project) but in the large that has been my experience. Even coming back to .NET this year after a few years away, I find not much has changed (despite the recent OSS "renaissance")