The best creators will innovate these sorts of flourishes, picking things that are thematically and tonally consistent and have a real purpose. Then other creators will copy them, as an omage to the original work in order to ground themselves in the artistic movement they wish to belong to. This is how we end up with such a distinct anime aesthetic; a slow accretion of unique elements forming a distinct culture as multiple generations of artists influence each other in blatant and subtle way.
