JDK 17 has most of the good features of Scala and Kotlin.
Scala seems to be designed so that you can write a short book with very fluent and natural looking demos. Make a small deviation from that and there is nothing fluent or natural about it.
Kotlin is OK but isn't sufficiently better than Java to be worth using when any Kotlin dev is going to have to know Java and Java-Kotlin mapping pretty well to use libraries. (It's a similar problem to Typescript.)
Both Scala and Kotlin are sufficiently similiar to Java to provide no real benefit. I'd point to Clojure as a language that is radically different from Java AND that takes advantage of the strengths of the JVM to be worth the cognitive load of having to know both a new and old language to be productive.
JDK 17 has most of the good features of Scala and Kotlin.
Scala seems to be designed so that you can write a short book with very fluent and natural looking demos. Make a small deviation from that and there is nothing fluent or natural about it.
Kotlin is OK but isn't sufficiently better than Java to be worth using when any Kotlin dev is going to have to know Java and Java-Kotlin mapping pretty well to use libraries. (It's a similar problem to Typescript.)
Both Scala and Kotlin are sufficiently similiar to Java to provide no real benefit. I'd point to Clojure as a language that is radically different from Java AND that takes advantage of the strengths of the JVM to be worth the cognitive load of having to know both a new and old language to be productive.