What is the main disadvantage of using object spread (...) for shallow copying hash tables?
Object spread limitations include: 1) Only copies enumerable own properties, 2) Misses non-enumerable properties, 3) Doesn't preserve property attributes, 4) Loses getter/setter functionality, 5) May not maintain property order, 6) Can't handle symbol properties properly, 7) May cause performance issues with large objects, 8) Not suitable for complete object cloning.