We were at Orient beach in November. I think it is just the luck of the draw. Some are more luckier than others or unlucky depending on how you look at it. Totally nude tend to stay at one end of the beach although some topless and thoses wearing thongs (who shouldn't) did parade up and down the beach. It is so true...the ones you might enjoy seeing nude are covered up and those that should not be are. I would say the average nudist is at least 60yo though I did see a man probably in his 30s who could have been Mr Universe...hubba bubba!
If you are really concerned about your daughter seeing any nudity I would find another beach.