What is the meaning of this phrase:
"The reason being all hard copy and storage media have a shelf life"
in the following context:
The reason being all hard copy and storage media have a shelf life, are bound to deteriorate over a period of time and the space required to store these media is huge.
I think you might have answered your own question there
"shelf life" is how long an item can sit unused and still be expected to work.
Cream has a shelf life of a week or two.
Bread a few days.
Camera film months to years.
Medicine days to years.
"hard copy" media could be printer toner/ink cartriges or even thermal paper.
"storage" media could be magnetic tape, disks, flash RAM cards.