The data on CD-DAs and CD-ROMs is recoverable, even if it’s from a bad batch that suffered disc rot, as the data is physically pressed into the polycarbonate, and is unaffected by the oxidation of the aluminum reflective layer. Longevity claims failed to account for that, but were also made in contrast to magnetic tapes, which wear substantially from use, and bleed in storage, destroying the data. CD-R and CD-RW discs use different methods of data encoding, and were never advertised as having similar longevity.