Even the author of the article says they would not personally attribute the experience to god or anything spiritual.
It has been well known for many thousands of years that various practices can induce these experiences. Everything from yoga, to music, to drugs, to sex, to ritual. In the absence of modern science our ancestors made up all sorts of silly explanations for why things happen.
You don't have to be completely crazy to have had some sort of experience with what the article is talking about. Even without prayer or intense meditation some people have overly active imaginations. In the end it all comes down to what a person believes about what they are experiencing.
Churches and forums like this one can act as a support group for people to reinforce and share each others delusions. Maybe some level of indulgence in this is healthy for some people, and can keep people from going "over the edge". Sadly however I still feel the potential for harm is greater than good.
Just look at all the cases of people who hear god's voice tell them to kill abortion doctors, or drown their infant child. Look at all the crazy occultists who have delusions of being the "chosen one" and all that. People who take their conspiracy delusions to the level of paranoid schizophrenia. Our society is riddled with this stuff.
Not to mention all the wars and fighting for supremacy of ideology.
There are many different levels of crazy and sane. Everyone knows what a crazy crackhead bum looks like. And yet plenty of people who consider themselves perfectly sane will buy into homeopathic or magical cures that are totally bunk. I think that's crazy.