Kotlin did not replace Java, except on Android. So JB now has a beast they have to feed without an enterprise revenue stream. They do get secondary benefits: they use it internally, etc.
We examined Kotlin in detail for a CLI app and based on conversations with Kotlin developers concluded that it was not sufficient of a Java replacement for us to evaluate further. For those in a similar situation, the greatly increased cadence of Java releases has probably permanently foreclosed Kotlin-qua-enterprise language.