Just to pre-empt the circular argument.
Absolutely right to say, "you can't say ... that one might not have helped"
Equally righ to say, "you can't say ... that one might have helped"
Personally, given the story does state that he died from head injuries, it's maybe okay to mention the helemt situation. What I know (and come on, we all know) is that if he HAD been wearing a helmet then that would not have been mentioned at all.
The Joe Bloggs psyche is that helmet = absolute protection of the head. The statement above, read by a normal member of the public who may or may not be thinking about getting back on a bike, is interpreted as, "... and he would have survived if he'd been wearing a helmet."
And actually, thinking on it, you DO get stories of, "Cyclist was hit but was wearing a helmet so was okay," because that's what every single anecdotal "... and if I hadn't been wearing a helmet I wouldn't be here today," effectively is.
Wear one. Don't wear one. I couldn't give a toss. A boy is dead because someone got tanked up, thought that driving in such a state was perfectly okay and drove over him where he was legally entitled to be. That is the important thing.
RIP.