We were making chemically and mechanically INCREDIBLE film at this point, remember it's the peak of things like film based aerial reconnaissance and spy-sats with film return capsules.

The problem with old images are two-fold, poor archival procedures causing damage to the prints, and (primarily, IMO) bad scans/transmissions/digital conversions/image formats from the first big push to preserve and digitalize content like this.

Worst part of that initial push for digital preservation is that it both caused people to get less diligent about physical archive procedures, and gave governments/organizations an excuse to cut costs by disposing of the negatives and prints since "we have them on CD now" without considering how quickly the tech would improve to create even better scans. Scans we have lost the chance to ever see, because the original media was binned immediately after the first mediocre scans were created.