You mistake me: I wasn't talking about Swift, a language I'm barely familiar with. I was puzzled by your more general assertion about "the kind of apps where a great type system would really shine". So far you haven't explained what you meant by this; you seemed to be complaining about enterprise software, but a lot of enterprise software isn't built with programming languages featuring great or even particularly modern type systems.

I'm not sure what reflection has to do with this. I'm sure you're aware there are "great type systems" which do not use reflection.