Is Delusion the Main Cause of Religion?

As we all (should) know, anyone who fervently believes in God (or any other supernatural entity) is deluded.

A delusion is a false fixed belief that is not amenable to change in light of conflicting evidence. (Wikipedia).

According to Wikipedia there are four different types of delusion and, when it comes to religious delusion we are talking about the type known as "Bizarre delusion": (Delusions are deemed bizarre if they are clearly implausible and not understandable to same-culture peers and do not derive from ordinary life experiences.)
https://en.wikipedia.org/wiki/Delusion#Types

So, when we talk about religion and delusion, we need to look at how religion came about in the first place. Way back in the days of yore the common people of all societies were profoundly superstitious to the point of morbid fear due mainly to gross ignorance through lack of knowledge and education. The ruling (educated) classes of course sized upon a golden opportunity and concocted a system of rules based on superstitious beliefs to control the unruly masses. The universal model seemed to be a monotheistic God who created all life and to whom we should all worship; there would be dire consequences for those who did not conform and for the impoverished masses who followed the barbaric and draconian rules there was the (artificial) hope of an eternal afterlife in a luxury resort.

Fast forward to today's modern society where we now experience civilisation being elevated to totally new levels of affluence and sophistication. Most people are educated and can certainly reach out to quality, uncensored information. We can see that religious rule is no longer, quite simply put; it doesn't work on normal, sane, intelligent individuals.

So, here begs the question: is it that delusion causes religion or does religion cause delusion?