NAS drives up to 12 terabytes are sold to home users. It also seems like people are becoming disillusioned with streaming services and are opting for NAS systems. In addition to streaming services, there are services like iTunes and Google Play where you "own" the content but can only use it on select devices. I only have an 8TB WD Red in my NAS, but I just got back to collecting physcial media in 2016 after eight years in iTunes. I've picked up a few 4K titles and I'm planning on picking up some more in the future - while avoiding the upscale trap- though I'll probably hold off on compressing the 4K versions until I can get my hands on a 5900X.