1. you should be more sad to hear that folks pray less (thus the empty temples) now than that early Christians weren’t the most literate bunch.
2. Do you have any idea the cost involved in producing a single copy of Holy Scripture at the time? There’s a reason no one even pondered the idea before Guttenburg’s printing press; it was nonsensically expensive and time consuming. That said monks labored for years (in poverty) copying Holy Scripture just to ensure that most PARISHES would have one.
And yet the early church found itself capable of producing works that has lasted for almost 2000 years (some even older). While I don't wish to minimize the expense, I suspect it wasn't alarmingly so. People usually spend their little money on other things, like food or shelter.