All you need is one Windows or Linux-based developer in your team to catch those kind of issues. But so many dev teams are macOS-only those days, whereas, apart from US and 2-3 other rich countries, 80%+ or even more of actual desktop users are Windows-based.
(There are many other problems with macOS monoculture, for example, the spread of ultrathin fonts that look nice and crisp on retina macbook but result in very low contrast rendering on Windows).
US-based devs: outside of your country (that is, >95% of humanity), most people do not have a Mac, an iPhone, nor use MM/DD/YYYY dates and 12-hour clock.