Generally different platform builds are handled by different developers - the codebase has to be modularized to be ported from Windows, to, say, Linux, to start

Generally different platform builds are handled by different developers - the codebase has to be modularized to be ported from Windows, to, say, Linux, to start, same with the UI. If you're already porting to Linux, you're already dealing with a UNIX executable, which makes it at least slightly easier to port to MacOS. There are also virtualization services available where you can rent dev time, and decent and upgradeable Macs are not that expensive second hand. I dev on MacOS all the time, and have the same issue with Windows. These days I try to write everything as a PWA to start so I especially don't have to deal with extreme UI/UX pains.