Windows crossplay

What technically prevents Age of Empires II from supporting Mac–Windows crossplay?

Does anyone with experience in game engines or cross-platform development know the concrete technical reasons Age of Empires II might not support crossplay between macOS and Windows? I'm…

Why doesn’t the Mac version of Age of Empires II support cross-platform multiplayer?

What are the actual technical or development reasons the Mac and Windows versions of Age of Empires II cannot play together? I'm looking for evidence-based explanations rather than…