SSDs are excellent for long-term storage, though that depends on what you consider long term. Theoretically, the NAND memory cells, which are voltage traps, could leak over time and become unreadable, but in the decade or so that SSDs have been in heavy use, we've not seen this type of degradation. Short answer, a couple of decades, yes; a couple of millennia, perhaps not.
Tested: These are the best SSDs you can buy right now… Note that due to the current global NAND storage the first of one of the many "benefits" of AI , SSD prices have skyrocketed, which renders some of the prices mentioned below and in the referenced review articles out of date. …
… It’s performance lends much credence to the theory that thermal design is important when it comes to high-speed external storage, or for that matter — high-speed storage in general. …