Some people like to claim that old storage technologies go away. But in reality old storage technologies live on along side of new... all that happens is that we end up having more tiers to deal with.
Drum magnetic memory has been replace but we still have spinning rust, tape, optical, DRAM, SRAM, SSD...
What's interesting about XPoint is it is literally a fourth form that has never been commercially available: melting a substance and cooling it quickly or slowly, forming either a crystal or amorphic solid, which then has different properties. We don't know what the substance is, but it's cool that we now have this 4th thing.
I think it's a bit conspicuous how you mention good ECC for printing stuff out, since good ECC is a staple of many forms of storage (especially hard drives, optical drives, tape) and we don't mention e.g. "storing bits on spinning rust with good ECC and reading it back in again".
I think the problem with paper is thot it's not really part of the computer any more. You need a human to take the paper out of the printer, store it, and put it back in the scanner. At least with tape and optical, we have robots to do that for us.
It lives on in the save icon. But in all seriousness you're right, floppy as a medium for data storage is dead.
Unless you're the US gov. According to Wikipedia: "In May 2016 the United States Government Accountability Office released a report that covered the need to upgrade or replace legacy computer systems within Federal Agencies. According to this document, old IBM Series/1 minicomputers running on 8-inch floppy disks are still used to coordinate "the operational functions of the United States’ nuclear forces..." The government plans to update some of the technology by the end of the 2017 fiscal year." [1]
There are people using optical media for long term storage. So I am not counting it out as a storage medium. In my classification I would put it in cold storage tier.
I doubt anything could be compact enough to be laptop friendly in the sense of being a physical part of the machine - but external USB 3 BD burners are quite small (powered over usb, too), I have a Samsung which works fine.
i don't know, a small radius "may" help remove mecanical constraints, and with a non stacked lens design sdcard reader height device.
I was mostly wonder about the psychological aspect of form factor. naked optical disks are non-personal, mini discs weren't. You interacted with them freely, carried them as is in your pocket. A large enough yet tiny enough reincarnation might be "fun".
Drum magnetic memory has been replace but we still have spinning rust, tape, optical, DRAM, SRAM, SSD...