Back in 1859 there was a solar flare from the sun which was so big and catastrophic that it destroyed most of the world's power stations.
Since there were no power stations in 1859, that wouldn't have been hard. Most of the power stations were built late in the 1800's. Telegraph systems used batteries, and high voltages were generated on the telegraph lines which could cause electrical shocks, arcs, and even fires.
The USA secretly hardened the telephone system during the cold war, when they learned what EMP could do, so the phone system was protected.
Our power system is very susceptible to such a event, and needs a major redesign, but it won't happen until it costs a trillion or two in damage. Even so, those DVD's won't disappear because of a sun flare. Early CD's were very unreliable, they are far better now, I had some lose their data in the late 1980's and early 1990's. I still have data from the 2nd generation of CD's.
Magnetic media, like floppy disks does degrade, and many of my 198X Floppies are no longer readable.
There is little doubt that optical storage is more reliable than magnetic, and compressing data is not as reliable.
However, many movie films are no longer in existence because they used acetate film substrate which disintegrates long before 100 years. Early technology is always less reliable until it matures. Solid state storage is pretty new, and is certainly subject to degrading. A cosmic ray might cause the loss of one of those billions of memory cells. Scratches affect film in a similar way, but its more serious.
I would expect that at some point, if data were to be archived on solid state devices like memory chips, then redundant memory structure would be used, its certainly doable, there are patents and applications, but its not yet out there for CD or CF cards.
Meanwhile, my first digital photos from the 1990's are still around while my Polaroid prints from the 1960's and 1970's are toast, Its sad, they have faded away. Even my color print film and color prints from the 1950's are no longer usable. Black and white and Kodachrome slides are just fine. Polaroid deserves to go bankrupt!