I don’t think there was any cleavage in my high school Yearbooks. Freshman through Junior photos didn’t go down that far. And while Senior photos did technically show that far down, there was a strict dress code. Wear proper attire or your photo got the axe. No apologies and we didn’t give refunds for yearbook orders.
I remember we all had a dress code even for us guys, no blue jeans or t-shirts, etc. I also remember that the dress code restrictions for both hair styles and facial hair had been amended a few years earlier. A good number of guys had mutton chops, sideburns and/or mustache, but absolutely no beards. A couple of guys had hair on the shoulders and some of the Black guys had fully blown-out 'fros. We were all cool back then.