OK, so in response to the last paragraph, I work in IT I KNOW I am correct about data archival. You have limited experience with this memory format as a light consumer relative to others on here.
Speaking from experience, doing firmware upgrades to servers in data centres using an SD card was fun. You would typically get through about 80 servers before the card either snapped from being badly handled or the data started to fail when read. 80 servers sounds good but then you have 70,000 of them to get done, then you need a better solution.
One of the systems I worked on for a well known Telecom company used to have 14 DLT tape drives to back up the production systems every night. Capacity wise it needed 9. The other 6 were there because at least 2 would fail most nights. Funny enough, this company paid so much in hardware maintenance contracts that the hardware manufacturer employed an engineer to sit onsite at the customer just in case so when things broke he was already there to get them fixed. When you have 70,000 servers then something always breaks.
Archival storage mediums have a guaranteed storage life of 30 years+
The issue with SD cards is like the other posters said, it could be years, could be never but It may also be tomorrow when that card fails - ever pull out the card without ejecting it first? Bad idea. If it is still writing to memory you can corrupt data. If you have, you know how easy that is to do. This of course also applies to USB hard drives. If you kill the power before it has written the cache to the disk, it is gone