> but Scala does give a lot of niceties IF AND ONLY IF you're willing to learn how to program the more pure functional side of things.

I disagree.

Context: Scala has been my language of choice for the past 9 years, and I'm the author of Scala.js. I don't know anything about category theory, I don't really care about referential transparency, and I've used a monad as a monad exactly 0 times in my career.

If you're really writing Java in Scala, then yes, perhaps Kotlin is a better choice for you. But there is a whole world of mix of OO, imperative and FP that you can do with Scala, and as soon as you start writing a bit more functionally (immutable collections, not category theory), you get a huge value from Scala. IMO no other language gives you that.

I have crystallised the essence of what I consider Scala to be in my talk Functional Object-Oriented Imperative Scala [1], for those who are interested.

[1] https://vimeo.com/362001027