I got an answer to this question that may be interesting to other forum members.
My brother has old episodes of Shazam that he bought years ago on the iTunes store. It no longer exists on the store, you can't buy any episodes, but Apple has kept the shows on their server. My brother can still stream these shows and redownload them via iCloud to his iTunes app.
I would assume the same goes for music. If you kept no physical copies of your tv shows and music and only played them on iPads, iPods and iPhones via iCloud, you would never lose access to this content, even if the content is pulled from the store.
Nonetheless, I'm still keeping a backup of my library in physical form that I update every once in a while.