I think the market for physical media will be less but is it going away? No. CDs are still around (See Adele) as well as LP records for a few examples. Optical disc video media is still around in 2015 and I have been hearing for 10 years that its dead. (lol) Still making billions of dollars...
One of the reasons I being a collector have not collected much electronic sell thru media is the idea of feeling a limit of ownership when purchased. I want to download and have the file in my possession (or at least have the choice) when I make a purchase. I think as we go along this will be...
Interesting but so far this year...Ebook sales are now in decline and physical books in many categories are on the increase again:
http://www.publishersweekly.com/pw/by-topic/industry-news/financial-reporting/article/67531-e-book-sales-dropped-in-first-quarter.html