Swift is inherently tied to the Obj-C runtime and messaging system (and GCD), which is OLD (read: Darwin/NextStep). The Windows and Linux ports have large swath

Swift is inherently tied to the Obj-C runtime and messaging system (and GCD), which is OLD (read: Darwin/NextStep). The Windows and Linux ports have large swathes of this low level infrastructure either missing or replaced with platform specific shims. This isn’t even to say anything of GUI toolkits etc. Apple likely doesn’t use these ports of Swift for anything other than bragging rights to say it open sourced a thing. GCD has been open sourced for a long time, but I’m not sure these concurrency primitives even work fully or as expected outside of an Apple OS with Swift. Hence Swift is essentially half baked abandonware on said platforms. I love Swift, but it has no compelling use case out of Cupertino.