Closures in JS are basically objects that have only one public property (called apply).
Modern JITs are good at optimizing static objects (provided props are never added or deleted and the types never change). There is still (from what I remember) a small performance increase to normal objects, but it only becomes significant if you are creating hundreds or thousands of them.
I'd say that in typical cases though that closures should be faster because devs tend to use them in ways that are easier to optimize (Closures don't ever add/remove properties and types are much more likely to stay the same).
Modern JITs are good at optimizing static objects (provided props are never added or deleted and the types never change). There is still (from what I remember) a small performance increase to normal objects, but it only becomes significant if you are creating hundreds or thousands of them.
I'd say that in typical cases though that closures should be faster because devs tend to use them in ways that are easier to optimize (Closures don't ever add/remove properties and types are much more likely to stay the same).