Surely by puberty leaving the choice to the boy concerned would be a better idea. Unless there is a medical reason like Phimosis. As they get older regular masturbation would probably stretch the foreskin enough anyhow.

It is not common in the UK to be circumcised, except for religious reasons.

When in Asia with many women, they would always make you shower before sex, and inspect the folds of the foreskin to make sure there were no tiny bits of cotton fluff off your underpants before fellating or any other sex.

I was encouraged as a boy to regularly stretch the foreskin by rolling it over a finger and running that finger around the head.

On a lighter note, one young guy's party trick at the rugby club after a game, to shock opposition, would keep a few peanuts in his foreskin, and get them out during a conversation, and nonchalantly put in his mouth, offering the other person! Usually he saved it for the snobbier clubs.