I have had tons of bike accidents over my life, both bicycle and motorcycle, never had more than minor scrapes. I have seen other people sand their palms down or break wrists or just flop flat doing nothing to arrest their fall or put everything into a knee, hurting themselves in the most minor falls.

I think falling is a skill or instict that some people just never develop. For those people, yeah wear a hemet.

This doesn't account for high-speed, direct impact accidents where its physically impossible to say, stop your face from whipping into the car infront of you or ground or w/e.

For what it's worth, I always wear a helmet on my motorbike, rarely on bicycle, never escooter.