I don't know why...
Google just don't put out a full 'Linux distro at this point.
I know 'Linux isn't a brand name to inspire self-confidence in the non-techie (if they actually recognised it) but they don't have to call it that.
All this dropping features in one at a time is like chinese water torture.
Just piss in the pot and get it over with, this drip by drip is just irritating.