I would sit there and direct the lifeguard, the complaining guests, the management and even their lawyer to video of the last 40+ years of Olympic Swimming and Diving. Michael Phelps, a "national hero" has worn a HELL OF A LOT LESS of a Speedo brand swimsuit on national television and been interviewed in them, posed in them for magazine covers, etc.
I think, beyond that, there is a point where a person MUST be cognizant of their surroundings when picking swim attire. I agree board shorts for laps is inappropriate as it does create unnecessary drag, but this work out was not being timed in milliseconds. To that end, perhaps a square cut swim suit or brief style bathing suit that does NOT "lift and push" the package (think like Andrew Christian's or Aussie Bum's suits do) would have been a more appropriate choice.
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