Certainly, there are “rules” on posting photos. The photo of the seminarians looks “cool”. In the photo, the seminarians are put on the same category with the young ladies as models. Seminarians are not “fashion models” they are students who are trained to become model Christians, hopefully, as ordained ministers of the Church. In the whole picture, the seminarians become “fashion” models. They are paralleled with the young lady models.
Could they become fashion models? it’s another question. But if seminarians are features on the clothing they wear outside religious or liturgical functions, it’s another thing. The clothing (the cassock) and posing (like the lady models) put them out of place. The meaning of the symbolism of the cassock do go with the posing (gestures) with the young lady models. The photo is categorically for fashion, but the symbolism is religious and liturgical. The wearing of cassock and the gestures of the seminarians seem out of place. They should put an appropriate meaning and dignity to the symbolism of the cassock they wear. As simple as that. It is neither funny or wacky, simply inappropriate.
They can model but not in their religious garb, unless it is the theme, and they are placed with other seminarians in their cassocks too (not young lady models)! In their casual clothes? Why not? That is cool! It all depends on their Director/Rector!