Sony have already stated why

NEX was becoming the name of the camera system and not Sony Alpha. They have always been been named Alpha, but NEX was taking over the Sony brand name with that series of cameras which has always been Alpha. Simple easy marketing strategies, but who are we to argue marketing when we know little about the Sony corporation.
Your bad news for changing the name is short term only, eventually once the NEX name is dead and gone, it all becomes normal

That won't take long at all as new NEX based designs come about, next year it won't even matter. Rumours and bloggers that get involved with corporate decisions must feel foolish as Sony produces cameras that they said Sony gave up on. It is kind of humorous IMO.
That is an old post on that site and already proved wrong with the design issue. I am a NEX-7 user, so he is wrong there for a start, I couldn't care lees what Sony calls it, the camera I use still works and its also very old news now in this fast moving industry. But to each their own.
All the best.
Danny.