Digging into this treasure chest: The Duke Ellington Centennial Edition: The Complete RCA Victor Recordings (1927-1973) Disc 15  

Not sure I follow your logic here.  Yes, the fact that an album is available for streaming today does not ensure it will be available tomorrow.  But if it is streaming, it's almost certainly also available for download too.  Which makes it exactly the same as a cd: get it while you can because it may go out of print at any time.

Wow!

External CD drives are inexpensive. I had to get one when I had to buy a new computer five years ago. I had an external CD/DVD burner long before that. CD prices vary: If you are searching for rare items the price tags are astronomical. Add to that the high shipping fees and customs fees and some items I would like to have are out of my budget. I recently found a Venzuelean CD from my wish list that is only 20 bucks, but the shipping costs would be four times as high, not including import taxes. Crazy. A friend of mine with an expensive high end system including high resolution streaming simply does not want to plaster his walls with shelves. Looking at my living room walls I can see his point. And I was surprised at the enormous catalogue of his streaming service. Many rare jazz items that never saw a CD reissue. We did our evening on Cal Tjader completely by streaming. And the sound quality was better than any of my LPs or CDs. All high resolution. Only disadvantage is that often the liner notes etc. are missing. 

I don't think it's a surprise that teens and recent teens prefer the new way of doing things. What surprises me is that adults have abandoned the CD. A very important aspect of owning physical media (books, CDs and DVDs) to me is that they go out of print.  The fact that an album is available for streaming today does not ensure that it will be available tomorrow.  Owning the physical media allows you to know that it will be there when you want to enjoy it.