I can run Swift compilers on Linux and Windows. But then, when it's time to publish a mobile app to the Apple store, I need to sign the app for the app store. To do that requires Xcode, exclusively available on MacOS.

Theoretically, I can suck it up and set up a virtual machine to run MacOS, just so I can sign my app and get it published. But after that, a year passes, and I have to pay the annual reoccuring developer account fee *again*, just to keep my ad-free, non-profit passion project apps on the store, for the accessibility of phones that I don't even use.