Like I said -- maybe, and, indeed coding-style fashions change. Something that wasn't important ten years ago may be important today. Java/Kotlin try to follow the mainstream, not break new ground. It's good to have such languages (I, personally, prefer them), just as it's good to have more adventurous ones. Java explicitly aims for a last-mover advantage, not a first-mover advantage. The goal is to learn 1, what works, and 2/ what's really important from other languages, and only then, maybe, adopt the most useful and important features.