I think that part of the problem is the desire to put a name a face to the cause of the accident. To be able to say "look here is who is to blame" is an understandable desire, however it is not always the correct approach. In addition it is easy to malign or misrepresent someone who is different from the norm. Lastly it is, in this day and age, quite safe to malign a deceased person. After all they can't fight back, and their friends and relations are not likely to offer unreasonable resistance.
That being said, in my experience that Mr. Sanchez was a described as a sad lonely individual is not surprising. In my career as a long distance truck driver I encountered a number of similar individuals, dedicated to their profession and hobbies but otherwise introverted individuals. Such people can seem quite lonely. His personal tragedies certainly suggest that he was sad.
That the media portrays Mr. Sanchez as they do is understandable, if not comfortable. As the media is a benchmark of normalcy, from the perspective of the media, he was different and therefore somehow "wrong."