No, as a framework author, this is still a productive addition. There are many a time where I would've liked to hide the concrete type of something from a consumer of my library. Mostly because the concrete type is something that has a lot additional methods/properties/etc, that, because of Swift's access control model and lacking existential support, mean I can't directly hide it behind a protocol.
Also, most of the time I've wanted this kind of feature has been for functions/methods that return results that should immediately be transformed/used.
That being said, I'm all for this proposal. Kudos to the people who helped bring this forward!