Even with the tower, there were enough people gathered that they could not clearly hear. This particular message was going to be essential for Benjamin’s people, and, therefore, all needed to know what was being said. There is so little information in the text that we cannot know if the account was written afterwards, or if there was a version of it written before Benjamin began to speak. It would conform better with typical ancient practice if Benjamin’s speech were spontaneous, and the written version captured it.
Combining an understanding of ancient cultures and hints in the text, we can say that Nephite culture was heavily oral. Even their written records tend to follow oral styles. This suggests that while there were certainly literate Nephites, they, like most of the ancient world, were mostly nonliterate.
If that were the case, then, what about the written version of Benjamin’s speech? First, the process of production itself limits the number of copies. There were no printing presses, so it would be a monumental task to produce hundreds of copies. It is most likely that what happened was similar to other ancient cultures, where a messenger brought the message and read it to a gathered people. The hints of the clan structures suggest that the messenger would go to a location, where the clan lived in the vicinity, and meet with them separately to read the message.
The very fact that the effort was taken to make copies and send messengers underscores the importance of this message for the people.