Why does it seem like people are leaving KJVO in droves? And not only that, but also many other “traditional” IFB doctrines that have sprung up in the last century or so.
My theory is that King James Onlyism was born and bred in an era where it was very expensive and time-consuming to look into facts for yourself. Until recently, there was no Internet. If your pastor told you that the King James Version was the only true Bible, you pretty much had to take his word for it. And how did he know? Generally the same way; someone told him, or maybe he had gone a step further and purchased a book or two that supported the KJVO theory. Buying books, however, is expensive, and purchasing books that refuted the deeply held beliefs of your upbringing was not always the wisest choice for spending scarce resources.
And so you have a situation where the propagation of factual information is limited by: fear of being labeled a heretic, apostate, Alexandrian, Nicolaitane, Satanist, etc.; reluctance to give up a strongly held belief; scarcity of funds and free time for research; and a scarcity of research material to evaluate.
We are part of the first generation that has the opposite problem. We take “information overload” for granted nowadays, and we have become adept at filtering and sorting that information in meaningful ways using tools like Google. If we have a question on a doctrine, we can pull up almost limitless opinions on that doctrine, and we have learned to use logic and reason to compare and validate facts and come to our own conclusions. We are connected now to more facts than ever before, and we are connected to more people via forums, which allows us to debate and sharpen our views much more easily.
In even earlier times, you were much more likely to find Christians involved in what we would consider obvious theological error. Most KJV translators, for example, were strict Anglicans. Why? Same reasons, but more pronounced. In contrast, with the wealth of knowledge God has blessed us with today, it is unthinkable that we wouldn’t start refining our views.