No, nobody is magicking up any fairy dust here. The author (which is me) is looking at things realistically. My maintenance costs just from a time perspective are already radically lower.
In anycase, so as long as the SSD is powered and thus able to rewrite blocks as bits start to go bad (creating some wear in the process but not a whole lot compared to normal operation), the actual data will be retained for significantly longer than 10 years.
Unpowered data retention (where there is nothing there checking for and rewriting blocks whos bits start to go bad) depends on cell wear. I didn't pull up the chip specs but my recollection is that it is 10 years for new cells and 1-2 years for a relatively worn cell. Depends on temperature of course. That means I can pull a SSD and shelve it without too much worry for a relatively long time, something that cannot be said for any hard drive.
CD's corrode from the inside out, primarily due to air trapped in the holes I believe. Even though it is laser burned there is no real care taken in constructing the plastic sides or metal film to keep up air so when it gets vaporized the oxygen sticks around and starts corroding the metal. Or the plastic gets fuzzy from UV exposure or age. Totally different ballgame.
Hard drives have even worse problems if left unpowered. I used to pull backup drives and shelve them, but their life spans are radically lowered if left unpowered on a shelf for 6 months and then replugged into a machine at a later time. I'm sure some HDD expert can say why. So I stopped doing that. Now the backup drives stay powered on 24x7.
Hard drives seem to have a limited life span whether you use them or not. I have tons of old HDDs sitting around, some well over 20 years old in fact. If I plug an old HDD in I can sometimes read the data off before the whole thing turns into a brick. I mostly use them to test disk driver error handling.
SSDs left sitting around can always be reformatted (i.e. just using TRIM to clean out the whole thing then start writing to it fresh). Their wear limit is based on rewrite cycles rather than how long they've been sitting around. HDDs are physically destroyed, you don't get a fresh start by reformatting an old HDD.
-Matt