Fine to think that people doing a naked bike ride are idiots, or insane, or narcissistic, or free & independent fun lovers, but I honestly don’t think it’s a particularly sexual event.
To be honest I do think it’s good for kids to see the naked human body in a non sexual context. Otherwise they’ll end up just seeing porn & think that’s normal.
At about aged ten my son saw some hippies skinny dipping in a river. He was pretty shocked & I overheard him saying to a friend that he’s had to draw pictures in school about the human body and he realised he’d got it wrong. 😂
I very much doubt there will be any erections on display, and naturists are so keen to normalise nudity as non sexual and non threatens, and distance themselves from flashers and sexualisation that any pervs would be given short shrift indeed.
Having said that, there’s no chance I fancy joining in!