Does Go support functional programming? There's no support for map, filter, etc. It barely supports OOP too, with no real inheritance or generics.
I've been happy working with it for a year now, though I've had the chance to work with Kotlin and I have to say, it's very nice too, even if the parallelism isn't quite easy/ convenient to use.
It supports first-class functions, and it supports classes/objects. Sure, it doesn't include good tooling for either, but:
1. map/filter are 2 lines of code each.
2. Inheritance is part of mainstream OOP, but there are some less common languages that don't support inheritance in the way you're probably thinking (i.e. older versions of JavaScript before they caved and introduced two forms of inheritance).
3. Generics are more of a strong type thing than an OOP thing.