In part 1 they talk about everything being a function including react components and closures. But I come from the "closure is a poor mans object and a function is a poor mans closure" perspective. In other words everything is an object. This is most likely because I started programming in the early 90s when first-class functions were not that common in popular languages (C had function pointers but it wasn't pretty)

But either way it works fine. Everything is a first class 'thing' that has properties that can be parameterised. If the 'thing' is an object the properties are alive and can be mutated (if mutable) for the lifetime of the object. If the 'thing' is a function the properties (arguments and local vars) are alive for the duration of the call.

When first class functions became mainstream though, I couldn't really understand the idea that they were fundamentally new compared to objects (in fairness this was only put forth by a few people)