The claim is/was that Lewis Hamilton could have avoided the accident if he had backed down.
To reiterate, Hamilton was in front of Rosberg and had the correct line for the next corner. Pretty much everybody in the world of F1 has agreed this is the case so how (or why) could he have possibly 'backed down'?
Webber the latest F1 driver (past and present) to say he doesn't understand why Rosberg made such an error:
http://www.bbc.co.uk/sport/0/formula1/28967288
Of course, Button has also come out and said it was an inexplicable error by Rosberg but, as he is a Briton and former teammate, you might not take his word on the matter:
http://www.bbc.co.uk/sport/0/formula1/28931224