At least at my company we are increasingly using more and more Kotlin. And that happens in many places. This is Server JVM, not Android. And I know other places too.
It certainly is, but it isn't Rewrite In Kotlin, that is so common to hear the community talk about, specially when their creators are quite open that it is a way to sell InteliJ licenses.
I can provide you the public statement on that, if you feel like not searching yourself.
That’s not true.