Why SSD are not suited for archival purposes

There is just a tiny, tiny amount of electric charge that keeps your data alive in each data cell, and once the data has been written, that charge is never refreshed, even if you plug the flash drive into a powered computer, or insert a flash media card into a device.
And it is not just solid state drives (SSDs), but also those convenient little flash cards used for cameras, and also USB flash drives. People using "flash card wallets" to "archive" their photos on camera flash media are all going to be so upset in about 5 to 15 years after they wrote that data, as their image files become unreadable and their precious photos have disappeared.
You should ideally not own more than about 5 to 10 flash memory cards, and you should be moving everything off the oldest ones to magnetic hard drives and then reusing them. Do not "archive" on flash media!

Life extension of flash media is possible by "refreshing" the stored charge in the data cells, but I do not know of any utility programs that can do this.
If you were to read the contents of each "sector" of the media and then rewrite the data back into the exact same sector locations, you would renew the charges and give your data in flash media another 5 to 10 years of life extension.
Though flash media tends to store data in larger blocks than a 256-byte or 4096-byte sector, so this refreshing would involve reading a full data block, then erasing and rewriting back to the exact same data block.
(A manual route is to copy everything off of a flash card or SSD, format the card/SSD, then copy everything back on it.)

Long term storage of archival data is really something of a problem because there is no good solution for it. Generic writable optical disc media also degrades over time, so burning files to CD-R or DVD-R is not necessarily the best solution either. There are special gold archival CD/DVD media, but it is more expensive than the generic stuff and even those become unreadble over time.
Mechanical hard drives (or tape media) are really the only good long-term options. Though, archival hard drives are best stored inside a fully enclosing metal box known as a Faraday cage, and unplugged. A lightning strike can blow up any hard drive with power or data wires running to it.