Just Before Internet, regional newspapers (major metro area here) charged US$55 for a 2-line ad to appear for one week. For anything legal that you wanted to sell.
Which tells me the business model was already failing even if the newspapers did not know it. Failing because the newspapers were forcing people with US$1000 (and less) items to find other ways to advertise and thus teaching readers to not bother looking in the ads in the newspaper. Impulse buyers and many others simply seized on the Internet when it came along -- it really was the only game available and it then sucked up everyone's buying.
AC writes: "Actually, they last beyond the time the material is worthless".
Actually even if the author wants a work released there is no practical way to release it that is accepted in US law. Plenty of authors have no illusions and plenty of works have very short useful lives. But existing law provides no way to deal with that.
The book "How To Fix Copyright" by William Patry has details on this and much more. I have no financial or other interest, I just like the book.
And don't even think about leaving your books to your kids.
Yes, my copy of Lord of the Rings turned to yellow fragments too. Wait. Is that what you meant?
5. The bad guys who wanted to control the outcome had no way to know the result was verifiable so their compromise was either a waste of time or worse (for them).
There. Fixed that for you.
Our business in life is not to succeed but to continue to fail in high spirits. -- Robert Louis Stevenson