I think they do, and this is why they giving it any resources at all while admitting they only see it used by tens of thousands, compared to millions using c#

At the end of the day, MS is a big corp, decisions needs to be justified and supported by both quantitative and qualitative measures

Also on the bright side, in programming, more developers doesn't really mean it will evolve faster, actually with a smaller team f# may evolve faster, it this wasn't true no language other than c# or java would have stood a chance