Re: Long live tape !
SSD's? Cant trust them. They leak and wipe themselves. 10 years on and your SSD will be very easy to read as it will be blank. Extremely limited capacity and highly expensive. Might fail to "chip rot " if made from cheap chinese crap.
USB flash drive? Cant trust them. See SSD, apart for the expensive part. They are cheaper for a reason...
HDD, Generally affordable and miles cheaper than SSD however cant trust them as they leak (well the magnetic fields fade) and seize up. The on board DEDICATED and CLOSED electronics allow you to easily plug them into any compatible host device. But those electronics, oh, I hope they dont have bad caps that fail and kill the on board computer that reads the platers.... I hope the chips dont have a manufacturing defect that causes "chip rot" over several years and the drive when needed in the future wont talk to the motherboard. Is the firmware even in PROM? Ah its on a f*cking SSD chip? See SSD. Even facebook is too scared to leave theirs off for very long and no drive gets to be more than a few years old as they are constantly spun up checked and replaced.
Memristors? Cant trust them, they appear to not exist yet.Hmm in 10 years maybe I can find one for sale. Oh but my data is here now. Hmm may have an issue using memristors at the moment.
RDX? Cant trust them. Marketing spin designed to empty tape haters pockets of money while buying a slightly higher grade HDD (see HDD) or SDD (see SDD) in a magical plastic case that makes them better somehow. Yet the Achilles heel of HDD and SDD tech was not removed from RDX. THE CONTROLLING ELECTRONICS ARE EMBEDDED I THE F*CKING CART!!!!!!!!
Basically I will not trust anything that is dependant on embedded electronics to let me access data decades down the line. Reading and writing should be handled by a device that uses REMOVABLE media. HDD's and SDD's are not media, they are small computers that contain media. Its the same as archiving your data to a fileserver and locking it away. Still think it will power up on 20 years? It probably will and it equally can emit the magic smoke. Is it using HDD's? (see HDD's)
Removable media today: Tape, Optical disc.
Tape is dense and reliable. Its just a spool of tape. Treat it like shit and you will get shit off of it. Accidents can happen (see conclusion) however but I trust it miles further than anything listed above. Downsides include mechanical handling of the tape may go awry and damage it. Tape reading/writing relies on contact with tape heads.
Optical, specifically media that does not rely on phase changes. This includes M-Disc DVD's and any HTL spec blu-ray media. If you really want, go further and have a proper pressed disc made. Treat the disc like shit and read shit off of it. Downside: as it is a multi layer media you are relying on the manufacturing process to seal it up properly. YMMV unfortunately but a little bit rot will not prevent the media from talking to a motherboard (see HDD and SDD). More expensive than tape but upsodes over tape include no physical contact other than what is needed to spin the disc.
Conclusion. Nothing can really be trusted but tape and optical (non phase change media) are the best we have at the moment. The universe HATES your data and DESIRES to turn it into random mush. Use a multi level, varied media system with regular scheduled tests. Replace bad media with direc replacements or the new version/better replacement. Maintain 3 copies on different media with all that checking and you should be fine.
Oh and if you cant be bothered, upload it to the "cloud" (cough someone elses servers) and hope they care enough to do this for you, correctly. Make sure you read their small print to be sure you can give them a legal slap should they let your data leak off their SSD RDX "media".