In Toy Story's case, the digital master should have had "correct" colors, and the tweaking done in the transfer to film step. It's the responsibility of the transfer process to make sure that the colors are right.
Now, counter arguments could be that the animators needed to work with awareness of how film changes things; or that animators (in the hand-painted era) always had to adjust colors slightly.
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I think the real issue is that Disney should know enough to tweak the colors of the digital releases to match what the artists intended.
Production methodolgies for animated films have progressed massively since 1995 and Pixar may have not found the ideal process for the color grading of the digital to film step. Heck, they may not have color graded at all! This has been suggested. I agree that someone should know better than to just take a render and push it out as a digital release without paying attention to the result.
In Toy Story's case, the digital master should have had "correct" colors, and the tweaking done in the transfer to film step. It's the responsibility of the transfer process to make sure that the colors are right.
Now, counter arguments could be that the animators needed to work with awareness of how film changes things; or that animators (in the hand-painted era) always had to adjust colors slightly.
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I think the real issue is that Disney should know enough to tweak the colors of the digital releases to match what the artists intended.