I'd say that the main reason for the different religions is the same as the reason there are different languages. People invent them both using imagination. As a result, we end up with nesting hierarchies of each - families of families of religions. If religion were the result of the interaction of man with an actual god, there would be only one, the way that there is only one periodic chart of the elements, which resulted from the interaction of man with actual elements. This is the power of empiricism.
I am aware of no truth that can't be expressed in plain English but can be expressed through a myth, but we may be using different definitions of truth. I reserve the word for things that are demonstrably correct. You might be of somewhat the same mind given your use of quotes around the word.
Yet religions consistently fail to meet humanistic standards for morality, which are based in the application of reason and compassion to evidence, not ancient standards that contain false and irrational beliefs and which fail to address many modern problems. Christian scripture misses freedom of and from religion, democracy, and the abolition of slavery while promoting homophobia and atheophobia. So what value is religion and religious scripture then if not as a moral compass? These mysterious truths in myths? I'm still wondering what those are, or what value people think they hold. All except the fundamentalists seem to agree that it isn't useful for understanding how the world works ("It's not a science book") or what happened in the past ("It's not a history book").
Of course. The claims have been debunked. And yes, these claims were believed to be accurate until it became untenable to believe that, and suddenly, we have revisionism - they were never meant to be believed literally. Of course they were, and to be obeyed to the letter. They stoned people to death for such violations. Yet we are asked to believe that there was wiggle room in interpreting the myths. Take a time machine back to OT days and try disregarding the commandment to obey the sabbath and see what happens to you. See how much latitude you get in interpretation. Tell them that it wasn't meant literally, but instead represents some hidden truth, then prepare to die.
And I understand that those who embrace religion find my words harsh and probably offensive. They will call them narrow, but they don't rebut them. They don't falsify them. They don't make arguments that show them to be wrong. They just go on telling me about truth and value that is claimed but never revealed in these threads. Sorry, but I find those words to be a disservice to those who believe them and go searching for truth in a holy book, and feel obliged to make the counterargument, since it is never successfully rebutted. If it could be, that would mean it was wrong, I would see that, and stop making what would then be a debunked claim. But the opposite happens.
Are you aware of the archeology regarding the Egyptian captivity, the Exodus, and Joshua and the walls of Jericho? It tells us that those things never happened.
And yet the fact that the religions disagree about almost everything is part of my reason for calling them fiction.
Once again, the failure of prophecy is good evidence that man has no contact with prescient entities. What you call evidence for belief is evidence for disbelief if one relies on the criteria of critical thought.
And again. Jesus doesn't resemble the OT messianic prophecy at all.
If you've read my story of being a Christian and why I left the faith, you know that it was just the opposite for me. I did the same as you, but came to the opposite conclusion. From an earlier post:
"I became a Christian, and approached the experience as if it might be what it claimed for itself or not. I remember distinctly agreeing with myself to suspend disbelief until I had had a chance to try this religion out and like a pair of shoes, see if it fit or not, or became more comfortable over time. Although I was a believer for many years, I think that it was already too late for me to believe by faith. My belief was based in experience - the euphoria my charismatic first pastor could generate during a church service, which I interpreted as the Holy Spirit."
Later, after moving cross country, I tried multiple other congregations, all dead. I learned that I had misinterpreted that euphoria, and realized that I had stumbled onto a rare preacher first. The Spirit would have followed me. By this time, I could see that these shoes weren't ever going to fit if I didn't suspend disbelief permanently, which is essentially abandoning critical thought altogether.
So not mythical, symbolic truths, but historical events.
It's not because a god exists. Why do so many people believe in Santa Claus? Because if you live in the right place, you will be told he is real, and you will believe that until somebody tells you he isn't.
Perhaps you should ask those who did and later declared that there was no evidence for their belief:
Atheists in the Pulpit: Clergy Who Are Non-Believers - Owlcation
So why study it? For the myths and prophesies? For its moral guidance?
And what is the value in that? Are the Ten Commandments accurate? Are the claims about its deity mythic or accurate? Does it really deem homosexuals and atheists abominations or is that allegory for something else. What rule exists for the individual believer to decide which words to read literally and which he can change to mean something else? What's the basis for calling the Garden story myth but the resurrection history? These are all rhetorical questions needing no answer. They are a statement that believers have no such criteria in question form, and that they make these decisions based in no rule.