Theoretically, optical media should be easier to recover than magnetic, because the technology to view their surfaces in detail is readily available --- a light microscope is enough to humanly view the actual recorded data on a CD and even a DVD:

https://3.14.by/en/read/cd-dvd-microscope

https://www.youtube.com/watch?v=Y8_HCLPdpkI (CD-R)

It would be interesting to see what "disc rot" looks like at that level of detail; and if better reading hardware may be able to read it. In particular, pressed discs actually store data in the varying height of the polycarbonate disc, so as long as those pits and lands haven't been damaged, even if the metallisation is gone, the data remains intact; and if there was a way to strip and re-coat that layer, pressed discs could be recovered. For CD-Rs, perhaps the dye has faded to the point where the typical drive (which can't really spin the disc slower than 1x) won't be able to discern the pits from the lands, but if that data can still be seen somehow, it's recoverable.