Hopefully they have looked into trying to drop it and considered it, but just decided it is too hard to do.

With the variety of devices, drivers and software for Windows it has to be way harder for them then Apple who has a pretty closed ecosystem. It's one of the reasons I like Apple more because everything tends to be more polished and work better cause it is closed and doesn't have to work with 1000s of hardware configurations.

They probably would have a hard time doing a backwards compatibility layer without getting every hardware vendor, driver provider, etc. on board too.