Agree with you, and Swift is also such a great language. I went from it to Lisp, sometimes I ponder about returning back (however my use case currently is for Lisp).
Mostly text based mathematical analysis. I couldn't stick to Swift as it would rule out a large section of the potential audience (Linux / Win - although Kotlin, which is similar enough, could bridge the gap to some degree), so I'm going more down the Web App route. For now, most of my I/O is in Emacs and later I may plan to work on the GUI side (via Electron or Web App, maybe but very unlikely CAPI or some CFFI).
How about yourself? Do you still do programming in AI?