He's an arrogant, unrepentant, vile little git who deserves to be in prison - probably for rather longer than he actually was sentenced to - because it was his recklessness that was the primary cause of the incident.
I do wonder (as I've said before) about a system that punishes outcomes rather than actions though - if the woman had merely been hurt, he wouldn't have been in prison now - and that was just bad luck as much as anything.
Indeed if her (undisputed) inattention due to her phone use had caused him to fall and bang his head and die, would she be in prison now?