You're right, if reference types are involved, it becomes tricky, however to the extent that Swift encourages value types, it still provides value. > in terms

You're right, if reference types are involved, it becomes tricky, however to the extent that Swift encourages value types, it still provides value. > in terms of information content it is strictly worse than what const can do in C. True, however the Swift community largely adopted a "use let first, only use var if absolutely necessary" approach, which is strictly better in terms of mutability-related bugs than what it was in ObjC/C, as mutability there is used much more liberally than in Swift.