Make is in POSIX, so it's generally available. Same reason people write shell scripts (even if the scripts are not generally POSIX-only).

Unless your company forces you to use Windows, which is still much more common than many would like to admit. And yes, WSL exists, but in my experience, if a company is unwilling to allow macOS, there’s a good chance they either don’t allow enabling HyperV, or the security software they use is such garbage that it results in a HyperV enabled system being effectively unusable.