So if a developer has to choose between Kotlin and NodeJS, why would they select Kotlin over NodeJS?
A fullstack developer may prefer the same language on the server and client. In this case Node.js and some JS tech on the client.
Imho, Node.JS is a lot simpler to use.
So, for less critical applications, Node.JS is very easy to use over the whole life-circle. If you need to build something mission-critical, you might want to go back to the Java giant and Kotlin.
If you already know JS quite well and you don't have Java experience, by all means, use NodeJS. If you're open for new things, especially coming from a Java background, give Kotlin a try, it's the best thing since sliced Kake.