It's a long debate among fans, but Chrysalis is supposed to be originally an unicorn pony which turned to some kind of dark magic just like King Sombra (or Discord itself, also, but he is a more *special* case) So, in fact, this could still be possible for her in upcoming stories (she can revert to her previous self...just ignore the IDW comic, it's not necessarily cannon if FIM animation says so)
That would have been so much better then the stupid "Team Changeling blasts off again" ending. And it would have been a better reason for Chrysalis not to come back than "blasting off". But no, they had to make a villain, that ist not freed or banished or turned into stone forever but "Blasts off by the power of true love!" All hail to the nonsense!