Contrary to ryandrake's rule of thumb, window managers are accessibility tools. You could argue that there should be a distinction between accessibility-tools-for-disabled-people and accessibility-tools-that-are-useful-to-everyone, but I'm not convinced such a distiction is useful, especially since Apple would likely try to subvert and destroy the accessibility-tools-that-are-useful-to-everyone, since those conflict with their user-hostile UI design, as https://news.ycombinator.com/item?id=21828816 alludes to with:

> I think they are very clear about the purpose of these, and it's not "to do cool innovative things missing from the regular API".