How much effort do you think would be required to build a compiler that parses bytecode generated by the Kotlin compiler, understands all Kotlin constructs and standard library semantics, and outputs Java source code that does not depend on anything related to Kotlin: person-weeks, person-months, person-years? Do you think that a Kotlin-bytecode-to-Java compiler would be the best project to spent that effort on?
What if the Kotlin compiler team improves the compiler and the resulting bytecode changes? Or what if the standard library is extended? A lot of changes to Kotlin would also require work to be done by the Kotlin-bytecode-to-Java compiler team.
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