Before it was collected as a compendium of official parts, sure, but most of the individual books (both the ones that made it into the current version and additional ones that ended up being rejected) were around. The Old Testament ones were already written down, and most of the Gospels were at least oral tradition very early on.
I believe it was over one hundred years before the Gospels were all written down, and early Christian sects had passionate disagreement over which texts were official or hearsay, but it’s not like they were completely without religious texts.
Or more things will happen like the Bhopal disaster where a chemical plant, over a decade or so, laid off or failed to replace everyone who knew what their carefully designed multi-layered safety systems did. When those systems aged and needed maintenance, the remaining production people took them out one by one. Then 500,000 people were gassed with cyanide. 2,200 immediate deaths. https://en.wikipedia.org/wiki/Bhopal_disaster