Yes, a lot of nonsense is propagated in many churches. But not all ignorance can be blamed on religion; it's only one cause. At one point in history the church was the only source of learning - the clergy and the clergy-educated nobility were the only people who were literate. Almost all of the great musicians of the Middle Ages and early Renaissance were priests because the church was the only place you could learn music or get a job doing it. The great artists were able to make a living mainly from church commissions. One could say that what was learned from the church was not scientific but based on belief - the church's persecution of Galileo is a good example of this - but it did contribute enormously to literacy and the arts.
Right now , though, it seems to me that one of the prime causes of horrific ignorance isn't the church but the Internet, which, ironically, has made almost all the knowledge and learning in the world available to us, quite literally in our laps. But it's as full of crap as it is full of facts. For every hayseed out there who learned in his fundamentalist Christian church that Noah's Ark was a literal thing and that the earth is 6,000 years old, there are probably a thousand people who haven't seen the inside of a church in 20 years but who believe Hillary Clinton managed a child sex ring in the basement of a pizza parlor and that a deep state is trying to overthrow Trump in order to install a socialist government that will take away their guns and give their daughters to MS-13. The plague of social media craziness, not Jesus, is responsible for that.
And, as you note, there are also vast numbers of people (many right here on DU) who haven't a clue what's in the Constitution but nevertheless believe it can be changed at the drop of a hat to do whatever they want it to do. People jump all over any "news" story - including obvious satire - that bolsters their existing beliefs. We all suffer from confirmation bias and need to recognize it. Religiously-based belief in things that can't be true is merely an aspect of the human desire for things to be a certain way and to accept as fact anything that supports what they wanted to believe in the first place. If you were brought up in a religious denomination that teaches that Noah's Ark was real and that there were contemporaneous dinosaurs who drowned in the Flood or some such nonsense, you will enjoy a visit to the Creation Museum because it reinforces your belief. If you hate Hillary Clinton you might believe she managed a kiddie porn ring in a pizza parlor. If you think the Constitution makes it possible for Nancy Pelosi to become president this January you'll post it on DU.
Ignorance is everywhere because people don't like to challenge their own beliefs, religious or otherwise.
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