You could potentially get herpes from it, but idk how long the virus lives on porous material like wood exposed to the elements. Covid for instance lasts 4 days on wood, but only 1 on cardboard. It lives much longer on, say, plastic, than on clothing.
I'd be much more worried about toxic chemicals because outdoor furniture almost certainly uses treated wood. And if it's pre-i-think-80s treated wood it's even worse.
But I am certain that a Bench with treated wood would not have the same characteristics from a cuttinf board. So maybe the idea could not be applied to a bench
I learned that wood boards are better than plastic, because plastic gets tiny grooves from cutting where bacteria can grow inside. With wood, those tiny grooves naturally close since wood "swells" when it gets wet.
My comment literally says "wood kills bacteria". The person worrying about getting AIDS form a bench is an idiot or joking, I was merely bringing up the fact that wood kills bacteria, which a lot of some people apparently didn't know.
Edit: unless someone with herpes used it seconds before someone without it, it's probably fine. I can't conceive how someone would get AIDS by sharing a pipe, bench or otherwise.