I laughed the first time I heard a MAGAt talking about how bad Biden was at speaking. I seriously thought they were joking, because Trump's word salad is far worse than any stutter Biden ever uttered.
...they were not joking. They seriously believe Trump is some great orator.
A friend of mine was in a bike crash during an event (large group ride, not a race), and he firmly believes the helmet saved his life. Even with it, he had a concussion that kept him off the bike for months. (I wasn't there and don't recall any details of the crash, if I heard any.)
That said, nothing is perfect. Another friend of mine slid on some leaves, crashed, and died several days later in the hospital. He always wore a helmet, too.
I always wear mine when riding.