It didn't. They're examples of features that have driven Kotlin's growth. Thing's Java developers have been begging for. I'm using them as examples of why Java developers are starting to choose Kotlin. I'm a pretty die hard Java fan, I've built my career on it, and know way too much about the ecosystem. But, I've been writing F#, C#, Kotlin, and some other languages in my free time to see where I want to move to. I’m pretty sure C# is what I’ll settle on.