Not to mention, these languages actually work for many, many domains. A shit-load of C# could just as well be F#. In fact, lots and lots of people do use F#/Sca

Not to mention, these languages actually work for many, many domains. A shit-load of C# could just as well be F#. In fact, lots and lots of people do use F#/Scala/OCaml/etc. to build real systems. Just because something isn't "the most popular" doesn't mean that thing doesn't work.