Some cost on Kotlin features. https://medium.com/@elye.project/method-count-on-kotlin-data-class-and-features-7b5085e1a4e7

The different method (and class!) counts are not the same for the simple little data class by itself, of course (when compiled alone, its size differences are more reasonable). So I guess the number of added methods and classes must have something to do with the overall size of the android project in which it is compiled? I wonder: how much other «boilerplate bytecode» did Proguard actually take away?