The "dark" technique has a long history in visual art. The word for it, "tenebrism", was first used to refer to sombre paintings. The grand master of the style usually nominated is Caravaggio.
Dark pictures are supposed to convey drama, seriousness, profundity, and worthiness. In some professional anthologies, say the Australian Institute of Professional Photography annual awards, the technique is widely embraced to the point of unconscious self-parody.
Styles come, styles go. Followers always outnumber leaders.