50yo skateboard/snowboard rider here. I’ve been going sideways since the early eighties but didn’t start wearing a helmet until my thirties.

In my group, we don’t preach at you to wear a helmet, you just simply can’t ride with us unless you do. The argument has always been the same. We do not care what you do with your life. Honestly, you do you. What we do care about is having a good time and enjoying our time on the slopes (I rarely do park nowadays). Scraping you off the asphalt or a lift pole, having to call emergency services, waiting for paramedics, calling loved ones, etc is not fun. It is actually a real fucking downer, and not something we want to deal with during our precious time off. So, do whatever you want, just not with us. Have fun and hopefully we’ll meet up later for beers.

EDIT: I have cracked two snowboard helmets on my head. One of them definitely saved my life. I was coming down a green slope on my way back to base when my board caught a rock hiding just below the surface. It slingshot me backwards, slamming me on my back and bashing my head on what I thought was snow. Ouch. I saw stars and it hurt a lot. When I get back to base my wife notices my helmet. It turns out that another hidden rock had pierced the back of my helmet clear through the plastic and foam and stopped at the thin thinsulate layer. It’s like a bit of fleece to keep your head warm. If I hadn’t been wearing a helmet, that rock would have gone straight into my brain.

I’ve never had a nasty fall on challenging terrain. It is always on fucking greens or paths.