This is definitely true. Also it's interesting you say "horror experience", because I do talk a little bit about it. Also I'll take your idea's in mind. I really like your "diagram of general horror elements" Idea.
Also what do you mean by "there are many horror genres that has not yet been explored by video games." I feel like a lot of games have used all types of horror, but I haven't been able to play everything so what do I know, haha. Thanks for the reply :3
This Idea was based of this video: