Counter point: in the last 40 years I have come off my bike only about 10 times and on 2 of those my helmet was so badly damaged that I think without it my head would have been seriously hurt. Those were both low-speed accidents, one was being hit from behind by a car and the other was hitting a nasty pothole.
I've also seen a friend have a high-speed impact: he was airlifted to hospital, survived and has mostly recovered. Looking at the state of his helmet I have no doubt that he would have died at the scene without it.
I've fallen many times and not once I've hit my head. They are probably useful in high speed impacts, but then you are fucked anyways.
Gloves are much more useful on a daily basis. Saved my hand many times.