> To my understanding, no it doesn't, as the value is resolved when the function pointed is created, not when the underlying function executes, which the code you linked shows too. I know it uses the "env" as a structure field, but it's partial application, not the actual closure which has access to parent scope

The code I linked literally shows that the closed-over terms are written into the closure environment when the fun is created, and if any term is a heap allocated object, it isn't copied into the closure, only the pointer is written into the env. The only reason you can't observe the effects of mutability here is because, unlike Python, there is no way to mutate bindings in Erlang.

Again, this isn't partial application - not in implementation nor in semantics.