... The drive will no longer spin up and all of the data will be lost.
Nonsense. This is a problem, but it has a straightforward albeit expensive remedy. The data is still there. In the worse case, remove the platters from the frozen drive and place them is a drive with working spindles and recover all of your data. Expensive? Yes. However, any file recovery service worth its salt can do it. If your firm has a technician who can do the job, then you have save $1 thousands in recovery fees.
As long as, you keep your optical media in light tight cases and away from bright lights, they should last a long time.
Again, nonsense. Well maybe a little sense. HDDs suffer two major threats--defective or worn mechanical parts and mechanical damage to the recording surface. Damaged spindles which I have suffered from and not lost a bit, flaking of magnetic recording medium, and a head crash into the platter. Optical media also suffer from two major threats--optical bleaching of the recording medium and aging of the plastic carrier/substrate.
Commercial CDs, DVDs, and Blu-ray discs have data recorded in geometric pits stamped on an aluminum film. The aluminum film is protected by the familiar plastic carrier/substrate. The aluminum film should last forever. If the disc is handled with care, then its plastic carrier will last about 20 years. After 20 years, the natural aging of the plastic will cause microscopic cracks that may render the disc unreadable.
Recordable CDs, DVDs, and Blu-ray discs are a different animal altogether. Their data are recorded as phase changes in an optical film. Every microsecond of light exposure bleaches the medium. There is no way to record bleached-out data. I don't know, but I suspect that the medium is also subject to natural aging even in the absence of light. Of course, the plastic carrier/substrate ages as plastic is wont to do. Unlike magnetic media from which data can be recovered after a failure--even a catastrophic failure--there is no reasonable expectation of recovering data after an optical medium failure.
The takeaway message is that recordable optical media are in a race failure induced by their own physics and chemistry. If you use optical media for backup, then the loser in this race will likely be you.