Since the Neolithic Revolution the humans decided that nature is to be formed, I bet something similar happened on Toril. So, if Ethel is a part of nature, she can be and needs to be removed, like the Bubonic plague or polio, or beards from faces.
But for me she appears not nearly as something natural, nothing comparable does exist. She is an artificial abomination. If she would be emotionless and cruel but sometimes helpful, ok, but she does not help, nobody, never. She feigns help but just acts for her own pleasure and always tricks and tortures the other people in the process and results. Of course she has some amazing goodies to offer to those who are strong in arms and weak in moral.
Otherwise btw she isn't necessarily the brightest bulb in the box either, getting in the way of our killer hero. Seemingly she forgot that she can vanish only two times a row, she wasted her chances. Sad performance for such an old and mighty monster.
Where we can perhaps agree is that the Ethel story is a nice side questline, or part of the main questline, I really like the character in that regard. I hope there would be a lot more of similar stories in the further game.
