Have you ever heard of Windows? Unlike Apple, they do care about backwards compatibility, and don’t randomly go removing features users depend on.

Also they aren't the only ones, this is pretty much standard across commercial UNIXes (the survivors), embedded OSes, mainframes and micros.

and the consequences are dire

Are they? IMO Windows going downhill has more to do with what is being added to it than what it is preserving compatibility for.