I will say this
I predict that larger trunks, Like arnold is wearing here, will make a comeback.
Let us hope
As with everything, BBing has evolved and glute condition is now a factor in determining the winner.
Making BBing mainstream seems like a lost cause, but full-bottomed trunks (i.e. a regular swimming costume) would likely help the sport become more accepted; even by the smallest of margins. Do we really need to judge glute condition? Yes, it's not gay to those who geniunely love the sport, but for 99% of the world's population it seems gay and that makes most people hesitant to follow it. It would be a small step forward and a compromise, but I feel a right step.
Arnold and Betty Weider were in alot of photoshoots together during the late 60's and 70's.