Part of the problem is that truth is taken out of context or so overblown that it just causes argument where there should be none.

A customer fell while test riding a bicycle, almost at a standstill and hit his head. He's got brain damage.
Is that a freak occurance? Yes.
Do I bring it up because I am "anti-no helmet" ?(whatever the f that is) No.

My racing friends have had concussions and medical issues rising from head injuries with a helmet including temporary blindness, partial paralysis (permanent), and medical complications.
Do I bring this up because I think helmets are useless? No.

These are not even widespread "facts". They are from personal experience.
Yet, I still believe no helmets are safe and up to people to choose.

My personal experience is to almost always wear a helmet.
But, I don't care if someone doesn't and it doesn't make them "less safe" because they don't.