The problem is that F# leads to shorter code by being incrementally better all over the place - so every example you show to someone he'll go "oh that's cute but I can do something similar with C#" but when you sum up those "cute tricks" you end up with 1/3 code, much less noise, and easier to maintain code. But it's hard to sell because there's no "one big thing that is 3x better than C#".