(Don't take this seriously, I know shit-all about any of this. :3)

Windows: The reason you can't easily do this thing might be because Microsoft is incompetent.

Mac: The reason you can't easily do this thing might be because it's potentially profitable for Apple.

Linux & friends: The reason you can't easily do this thing is almost certainly because some random person didn't think it important and everyone since is too smug to make it properly.