While the young actresses in the original "Un Moment d'engarement" and "Blame It On Rio" were both slightly underage themselves at the time like their characters, the actress here, Lola Le Lann, was actually about twenty, and ANY male of ANY age will find her VERY attractive as she frolics around completely naked in the surf. For what it's worth, this version does make one concession to our more cautionary times. I doubt even in real-life France that middle-age men routinely sleep with their friends' teenage daughters, but the French also just don't have the ridiculous puritanical hang-ups of Americans when it comes to anything having to do with S-E-X, and thank god for that. I definitely wouldn't lie down on the train tracks and let a train pass over me, even though it seems exciting when they do it in movies, and by the same token, while I enjoy the fantasy of movies like this (or the two earlier versions), I certainly wouldn't do it in real life. There are A LOT of things that seem exciting and enticing in movies, but would be extremely foolish and probably disastrous to do in real life.
Are sexually active teenage girls really a lot better off with an inexperienced guy "their own age" who doesn't even know how to successfully use a condom? For me though it is pretty simple. It's very doubtful older teenage girls have become more virginal since the 1970's and 1980's, and the idea that a sexual relationship between a younger person and an older person is ALWAYS "predatory" (provided the younger person is old enough to be sexually active in the first place)is a lot more debatable than it is often made out to be.
It is interesting though that the French are STILL making films like this, while the Americans wouldn't touch this subject today with a ten-foot pole. BOTH movies are remakes of a now largely forgotten 1977 French film with the same title as this one, "Un Moment d'engarement" ("One Wild Moment"). There is a reason that some of the other reviewers have noted that the plot of this movie is very similar to the 1984 American film "Blame It on Rio".