If you aren't writing low level code, why not use a GC language?
I’ve had more than enough unpleasant experiences with write-runs-breaks-at-runtime style languages. I don’t like writing them, I hate having to support them in prod as they give me constant-persistent-stress. I hate what idiomatic C# is, and how much ceremony there is to read and write it. Java is worse. Go’s type system is too anaemic for my tastes. Haskell is nice, but gets a bit academic and lacks some day-to-day niceties. Kotlin is supposed to be nice, but again, we’re getting maybe 50% of Rust type system features, and you’re basically just piggybacking on Java/JVM which I hated dealing with previously. IDK what else that leaves in the mainstream. I used to play around with Nim, and that was quite nice though.
Expression-oriented, HM type inference with gradual typing, faster than other FP languages, can even reach for low-level bits, or write extra glue code in C# which is more pleasant at low-level imperative code.
Not sure what exactly you refer to as idiomatic C#. If it has too much ceremony chances are it’s anything but!
Edit: I do love the ML style syntax though, Haskell, F#, Dhall are awesome, I wish it were more readily accepted.
I recognise C# as useful, but _personally _ dislike it because of the sprawling, OOP-heavy, ceremony-heavy core it encourages you to write. Half my dev friends write C# for their day jobs, half my workplaces have had me dealing with it. It’s not an opinion borne from unfamiliarity or knee jerk reaction; my distaste for MS is just the cherry on top.