"After all, major religions tend to discourage critical questioning (Y'know, threats of heresy, excommunication or worse, that sort of thing)".

You should refresh your knowledge on religion....you seem to be thinking in the dark ages.

I suspect there are santions against non-religious activities in some world countries...but, few if any in western countries or with Christianity today.

And, again, many, or most Christians, who belong to organized groups, don't pay much attention to much of todays church dogma from the top anyway (for example, some churchs ban birth control, and they use it anyway).

So, the thinking of many or most who believe in a God is not much different from Athiests, even though some try and make it seem like there is a difference. IMO, the reason is often underlying bitterness from an unfortunate past experience with a church. Another possibility is elitism (I found the way, see the light, want to tell everyone and create a special place in society for the enlightened...which fall short with most folks anyway.Elitism is also evident within extreme religious groups.

So, Steve. Dwelling on this aspect of your theory IMO, does not serve you well.Some theories, or unproven beliefs...like the one you promote, are best kept close to your chest...unless you purge yourself of such untruths.