Yes as the Server Core configuration it can, but you don't get to replace Win32 puzzle piece that goes on top with something else, you might augment it with alternative UI frameworks, but ultimately it is Win32 at the bottom layer.

Just like on macOS, while UNIX on the bottom layer, you don't get to plug something else instead of WindowServer and related low level APIs. Even with XQuartz, it builds on top of it, just like they build on top of Win32 on Windows.