As long as external USB drives are made, it's a moot point. I can even buy a USB floppy drive if I need one.
I can't see the need for burning data to a disc ever going away completely. How reliable are memory sticks and SD cards for long term storage anyway?
And it's not like future Blu Ray players are going to suddenly drop CD playback.
You make a good point with floppy drives. I don't think I've even used one in 9-10 years. Going back to the really old days I actually used floppy discs that held only 360kb of data (that right, kilobytes, not megabytes, plus they were the size of dinner plates).
As technology improved and discs held more, 720k floppy drives, which then doubled to 1.4Mb, CDs, then DVDs, BluRay, etc., there would always be equipment to use them, particularly with music and films. I hope that even as the formats change, physical media will always be around.
If I'm home sick with the flu I can watch what I want whenever I want from discs I own. Maybe fall asleep doing it and not have to purchase it a second time, lend it to a friend, etc. I could just bring my portable DVD player with me on a plane flight, not having to worry about missing something or not getting a signal at all while trying to stream something.
There are lots of reasons that physical media you own makes much more sense than streaming it or storing it in "The Cloud". Technology is obviously much more reliable and available today, but I like the freedom of actually owning something I'm paying for, not just borrowing it for a couple of hours.