Robert, did you know among pagan nations, nothing was more common than for persons to profess to have contact with spirits, and to be under the influence of their inspiration?
And yes it frightens most Christians.
I haven't made a study of it. But I have some opinions. I think in pre-industrial societies people were more in-tune with the environment in which they lived. And this made them more sensitive to knowing good and evil going on about them, and in them. In today's society we have been desensitised and consciences cauterized to such a degree that demons can easily remain undisturbed from the light.
In the Bible note how people with demons and possessed came forward or were brought to Jesus.
In this age demons find refuge in the abundance of darkness, and operate in it.
But not to fear Jesus already has won the victory.