Yeah, but if you use F# that then you’ll have all the features C# has been working on for years, only in complete and mature versions, and also an opinionated language encouraging similar styles between teams instead of wild dialects of kinda-sorta immutablity and kinda-sorta DU’s, and everything in between, requiring constant vigilance and training… ;)

I’m a fan of all three languages, but C# spent the first years relearning why Visual Basic was very productive and the last many years learning why OCaml was chosen to model F# after. It’s landed in a place where I can make beautiful code the way I need to, but the mature libraries I’ve crafted to make it so simply aren’t recreate-able by most .Net devs, and the level of micro-managing it takes to maintain across groups is a line-by-line slog against orthodoxy and seeming ‘shortcuts’, draining the productivity those high level guarantees should provide. And then there’s the impact of EF combined with sloppy Linq which makes every junior/consultant LOC a potentially ticking time bomb without more line-by-line, function-by-function slog.

Compiler guarantees mean a lot.