Welp I guess this is the comment to finally bring me out from the lurker caves.
Besides just being straight-up sexist (this is 2023, we should be beyond this), barring men without kids wouldn't just (unjustly) exclude plenty of terrific volunteers, including myself, it would simply kill scouting.
I recently took a job as a DE in my council, and after going around meeting all the units and leaders, let me tell you 95% of units are surviving off the veteran volunteers that have been around for a while. They all say the same thing. They'd love to have some parent volunteers, but the fact of the matter is no parents are stepping up. So barring "grown men without children in the unit"? Instant death sentence. I don't blame the parents, you even said it yourself, your time is limited. Now more than ever it seems. But until something changes and parents can/do start actually volunteering, those veteran scouters without kids in the unit (or in rare cases, young men who were scouts and don't have kids yet such as myself) are what's keeping scouting alive. Trust me, in many cases they do want to retire and pass the torch to the next generation, but there's no one to pass the torch to. So IMO, these men should be rewarded for keeping scouting going, instead of criticized for the mistake of being born male and caring for the future of today's youth.
I could go on and on about statistics and the existence female predators and how the BSA could market YPT better to the masses, but my food is getting cold. I will say this though. As a member of the first generation raised surrounded by these negative stereotypes about men, the pervasive fear of "anyone can be a predator so assume everyone is", and the complete lack of independence until 14-16 because I might get kidnapped or x or y or z (which isn't helped by America's car-dependent suburban lifestyle but that's completely off-topic) in American culture is developmentally harmful. Especially for boys. Does it work to prevent abuse? idk. YPT certainly does but the stats the FBI puts out doesn't paint a pretty picture.