I would attribute the fellow's death to manic depression. A person of normal mentality would not be so distraught over his physical attributes, in my opinion. If not his privates, he probably would've cited his height, or his puny stature, or his ugliness, etc.
This is not unlike newspaper articles stating,"Old friends of over 80 years get into fatal brawl over a move in checkers" or some rot like that. Simple misrepresentation. It wasn't the fact that one of them contested a move the other made in checkers, it was a trivial matter which spiraled out of control into rash anger. Similarly, this guy was just abnormally fixated on his own physical shortcomings (whether or not they were justified,) and couldn't cope with is own poor self-image.
The fixation on his penis size is largely irrelevant and just a tawdry detail which makes for an eye-catching headline, in my opinion. I wouldn't support more sex education (at least, not for the sake of preventing similar suicides) over there, but I would back hotlines for neurotic teenagers prone to over-reacting.