"Can be made to work", absolutely. "Works fine", gonna have to disagree. The hoops one needs to jump through for every single new project that uses Makefiles in some new and creative "works flawlessly on unixy systems, why aren't you on one of those?" are appreciably larger than zero.

If you’re very careful with forward-vs-back slashes and your username isn’t “Firstname Lastname”, sure. But in practice there are tons of issues especially for non expert users