You have observed random and limited reproduction of such material, not blanket availability. The point I am making is that books can be read as long as the paper survives. Electronic media’s lifetime is at the mercy of the marketing people and the transient nature of the media itself. To keep anything a long time one must transfer content from media to media, forever and often.
” Electronic media’s lifetime is at the mercy of the marketing people and the transient nature of the media itself. To keep anything a long time one must transfer content from media to media, forever and often.”
My personal files from the early 80’s are essentially the same media as I use today. That was almost 40 years ago! So your statement is wrong.