"Any type of value as key" is quite misleading since anything other than primitive types (number, bool, string) is compared by reference. Observe:

  > const m = new Map();
  undefined
  > m.set([1], "one");
  Map(1) {Array(1) => "one"}
  >m.get([1])
  undefined

C++ and Rust don't stand for this nonsense. You can't even define a custom hashing function, which means if you want a useful map for anything other than numbers and strings you have to write a wrapper around `Map` that hashes the objects to numbers or strings, and then you're more or less back to raw objects.

It's definitely better than raw objects because it doesn't mix up data and methods, but it's not much better.