I was going to comment the same thing. I moved from F# to kotlin and have about 80% of what I want / used from F#. With more tools eco system that makes management happy. Arrow adds to that, with it's library and compiler additions.

I have also been building type providers in Kotlin. Where a gradle plugin scans a file / schema then generates types and DSLs off of it. It's a pragmatic functional language.

The biggest catch to me. Is there are very few places using Kotlin in a fully functional style. On the back end more often than not you'll find Spring. Which undoes a lot of these features / patterns.

Incidentally, Java is getting pattern matching that is more capable than Kotlin's (and probably on par with Scala's).

2 out of 3 of those are coming in Valhalla. You don't need pointers.

In addition to that, the .NET runtime supports tail calls but the JVM does not, IIRC.