I don't know...from what I can tell it sounds like they removed the usage of Mac OS specific APIs from mainline::

https://lists.gnu.org/archive/html/emacs-devel/2016-01/msg00...

Doesn't sound like crippling to me.

> Deciding not to implement the feature in the first place, well, that's a reasonable decision given their desire for functionality to be cross-platform. But accepting it, then turning around and removing it later even though it was already implemented, that's just spite.

Well this ignores the challenge of maintaining an open source project.