I'm surprised they can't just put a filter on the digital versions to achieve a similar look and feel to the 35mm version. It is clear that the animators factored in the colour changes from the original media to 35mm, so it seems a disservice to them to re-release their works without honouring how they intended the films to be seen.
They could, but it would require some work to get it right. This is very similar to conversations that happen regularly in the retro game scene regarding CRT monitors vs modern monitors for games of a certain era. The analog process was absolutely factored in when the art was being made, so if you want a similar visuals on a modern screen you will need some level of thoughtful post processing.
And ultimately, what you need to achieve acceptable CRT effects is resolution. Only now, with 4K and above, can we start to portray the complex interactions between the electron beam and the produced image by your console. But the colour banding that caused the hearts of The Legend of Zelda to show a golden sheen is still unreachable.