It's also missing the condition. macOS is only "free" after you buy their hardware, i.e. acquiring it is still tied to buying the hardware. If it was actually independently available for free then you wouldn't be prohibited from running it on other hardware.
See also Windows and Internet Explorer.
Neither MacOS nor iOS are anywhere near being dominant in their markets in the same way Microsoft was with Windows.
Ford isn't getting sued either for only selling cars with Ford motors inside.