I think there have always been something like this. In that one cave in France with all the cave paintings, there is a big breasted woman with a buffalo head that is believed to be a fertility goddess or something on those lines.
Echidna of Greek Myth, was the "Mother of Monsters" and had a uper half of a woman and the lower half of a snake (think the Lamia girl from up top). Medusa and Gorg ons, despite being described as hideously ugly are usually depicted as quite gorgeous.
Ishtar had owl feet and and wings, and was the goddess of love and war, AKA, she's give you godly sex and then bing upon your utter destruction. Cat and Fox girls existed in myth. Most of the Egyptian gods and Pran. Ect, Ect.
Part of it if I have to guess is a fad, and this will come and go as needs be, like Moa or the Mad Max Ripp offs of the 80's and early 90's. There were also a few monsters here and there used in gaming, such as harpies, Felicia, and some of the creatures in Disgaea.
It might also be somewhat of an Uncanny Valley idea. Like how giving R2-D2 or Bender just enough human qualities make their humanity stand out more being none human, it might also apply here as well (and this may involve personality but it definitely applies to the three B's of Hollywood: Boobs, Butts, and Blood).
And there is the fact it can be hot. I only fear that this will inevitably lead to a Sturgeon's Law thing, and get overplayed to the near exclusion of all else in the same way Western, the Musical, and even the Epics from the Golden Age of filming where the market gets flooded with sub par offerings in-between the good and the amazing with one or two flops dealing the whole thing with no survivors. Westerns, Musicals, and of cours Epics still get made into films today but how often do we see them?
