What is wrong with theistic beliefs?

[Whateverist]

They're mainly indoctrinated by cultural pressure. Although the most devout ones may really be insane, and use religion to justify things they would be doing if they hadn't been raised religious. And then there are those who are flat out dishonest, and are using it for money and power.

I agree that is most often the cause of what affects the thinking of theists.  I chose to characterize that thinking as being affected by an illusion because I think there is something they are experiencing which they are mistaking for evidence of God.  But like you, I think it is most often the child rearing they undergo and the nature of what beliefs the parents impart most forcibly that influences their thinking in that direction.