I do think the need for a case with three 5.25" bays should have long gone and the space freed up for other purposes. But I still have use, real and potential, for a RW OD. Who on earth wants to faff around with an external OD, particularly when, whatever the future, there should always be plenty enough space in a desktop case to incorporate one or even two?
A Blu-Ray RW drive is the obvious choice and surely something almost everyone would find useful even if they have a dedicated player. I have a largish collection of CDs I want to rip to HDD but I'd point out that doesn't suddenly remove the need for the CDs themselves. You still have to own them to keep it legal (at least in the UK) and if you have the discs it would be stupid not to keep the capability to play them.
I'm sure there must millions of people out there with cars fitted with CD players rather than MP3s and might want to burn backup copies for that.
If you're into retro gaming and emulators installing stuff from disc is usually unavoidable particularly if you want to stay on the right side of the copyright laws. Then there are anti-virus and OS rescue discs which aren't going to be
affected by the things that could stop you using a USB device or rescue partition.
I have other, admittedly niche, uses for both reading and writing stuff to disc but most of all I would point out that a physical storage medium is still the safest way to keep anything long term. Old photos, important documents.......whatever, all of which can go in an instant if stored electronically, are safest on disc.
Discs of all types are undoubtedly becoming less important than they once were. That will continue over the next 10 years but, I hope, plateau out rather than completely disappear. At present it is still very useful, relevant technology and I for one won't be following the sheep who think that cloud and flash memory storage is all they need.