A comment that someone made on the first video:

Karen Evans, 10 months ago (edited):

Dr Clarissa Pinkola Estes talks about this story and gives a great psychological understanding of it. She says that the Erl King is a soul stealer.... who represents the culture that we live in which crushes the child spirit (don't do this, don't do that, do as I tell you to do etc.) The father cannot see that this is happening because his spirit too was crushed as a child. The horse represents the instinctive nature in us that is alive no matter how much the culture has deadened us, but, in this case, could not outrun the culture. In her explanation she concludes "the Erl Konig is everywhere. It lives in the psyche of every individual, and if we allow it to take over, in part by not resisting where it touches us in our lives, we become deadened, and we pass that deadening onto others" 

ETA: So yup, that sounds pretty disturbing to me! I didn't have a personal reaction to it, however, except that I thought it was super cool. But then creepy movies are my favorite kind to watch, so I wouldn't expect to have much of a visceral response.