[nicolai-parlog]

That misses the point. The strength of records is that the language can build features that are only possible because of records' restrictions. It's not that the bytecode says "I'm a record" - which is all you get if Kotlin compiles a data class to one. @JvmRecord gives you all the limitations with none of the benefits. The annotation only exists for compatibility reasons.

[unscaled]

The problem is all of these "benefits" are imaginary right now[1]. You are talking about future possibilities that Java could get due the strong guarantees offered by Java records. That's cool, but I couldn't find in your article (or the JEPs) any such benefit that is available _right now_.

The reality is that Kotlin can build the very same benefits you're talking about as well, in future versions. All the compiler has to do is to restrict these benefits to data classes which only have 'val' members, do not have hidden state and do not use inheritance. In fact, Kotlin is ALREADY enforcing these constraints on a any data class that you annotate with @JvmRecord.

Now, if we're already talking about imaginary future benefits here, Kotlin is also planning to have (immutable by design) value classes when Project Valhalla is ready (you can already have value classes with a single field in Kotlin 1.5).

[1] To be fully honest, Java records themselves are themselves an imaginary feature for the vast majority of Java users until Java 17 comes out, since very few projects would use a non-LTS version. And even then, you can expect years until libraries can start to use them. Kotlin and Lombok data classes can be used right now.