"Placing multiple declarations (classes, top-level functions or properties) in the same Kotlin source file is encouraged as long as these declarations are closely related to each other semantically." I totally agree for top level functions, properties and small objects. But people are often doing things like whole data model in single file and it is really hard to operate on that. It makes harder to find classes when files are not named with their names.

What if the types in the data model are very small data classes? Also, do you normally locate type declarations by searching via file name? I find most people navigate via class names and not file names when using IDEA/AS

added clarification regarding file size