This is technically very false. Windows most definitely is not “free” as in air or beer. It’s license fee is reduced to 0 but there most certainly is still a license and businesses pay out the ass for them. macOS also has a license, but it comes with the hardware. Technically, you cannot install macOS on non-mac hardware, per EULA, but there’s no license check outside of hardware support, which is the space the hackintosh world comes in.