I have not tried to program in any of them except Kotlin, and I had an immediate allergic reaction to that. However, all of them seem to be common enough I've

I have not tried to program in any of them except Kotlin, and I had an immediate allergic reaction to that. However, all of them seem to be common enough I've heard of them before looking at the JVM wikipedia page, and it seems like Google is committed to Kotlin for Android going forward. And all of them except Scala seem to have originated after the timeframe mentioned above. I don't have a strong contrary opinion to yours; I just don't see where yours is coming from.