100% this, I spent many months going through the most recent books on F# including one which the latest version was only released last year I think.

They all seem to try and shield you from the fact that you are much better placed if coming from C# (which everyone seems to refer to as .net these days) and have a solid understanding of the .net class library.

All the main web frameworks sit on top of asp.net and pretty much all official documentation for that is in c#

Such a shame because I learnt so much about types from trying to crack f# for real world application. fsharpforfunandprofit taught me heaps which I apply to other languages, but I don't want to become a c# developer which comes with all the years of changing best practices to be able to really be productive in f#.

Sorry if I am coming across as bitter but I just can't see learning f# in isolation from c# which is an absolute shame.

What is the issue with learning C# alongside it, if only the bits necessary to improve the F# experience? Both are excellent languages.