For clarification, as I should have mentioned: I am speaking only to code that has one of the following characteristics: 1. It’s new code 2. It’s a significan

For clarification, as I should have mentioned: I am speaking only to code that has one of the following characteristics: 1. It’s new code 2. It’s a significant re-write 3. It’s a substantial refactoring of existing code or a refactor where using one of the newer apis would be trivial (e.g Reflect.apply vs Function.prototype.apply)