I guess I am just old fashion or just old. (actually both). My DD 17 wears a one piece swim suit, my DW wears a one piece swim suit, and I wear mid length swim trunks and wear a Tee or swim shirt as well. I'm not trying to define one's own morality, I just prefer to show some modesty instead of butt cheek, pecks, or the junk in the trunk... Just me.
I think one thing we are forgetting is the age of these kids. They will grow up fast enough, it seems like we just want to push them to be men and women so fast. Again, JMHO.