Comment by actionfromafar

The color has always faded - well, not always. The gold standard for movie archiving is to store the movies color separated on three reels, one for red, green and blue, but not use color film, but a special black and white. There's no fading at all on these.

Sometimes the original negatives are in really good condition, but you still have to redo the color-grading, because the original color-grading was done chemically onto some transfer which now has faded or was just pretty bad to begin with, if you even can find it.