[Groxx]

It depends on the purpose. Config structs are indeed simpler and make tons of sense for cases where you control all the related code. So yeah, for code where you can do a mostly-automated refactor if you need to change the API, I totally agree that Config structs make more sense and functional options are huge overkill.

For stuff that needs finer-grained control, or long-lived API stability, functional options give you a lot more flexibility.