user
07/05/2016, 1:25 PMkotlin.comparators isn't imported by default) is that the split of the standard library into packages happened very late in the development of Kotlin 1.0, and we wanted to minimize the impact on existing applications.
I agree that the list of extension functions for List is kind of hard to read, but given that those extension functions are declared in many different places, a file-based grouping wouldn't help much. A better solution would be a tag such as @group that could be applied to the doc comments of different functions, regardless of where they are declared.