Can’t agree with you there. The whole choice of colour grade in the Disney versions across streaming and discs is pretty terrible. “Dark and desaturated” was clearly the brief. Particularly in Empire and Jedi.
The silver lining is that unlike the 11SE, all the color information is there so with some tweaks it can really be improved.
I’ve got the discs on hand now. They could be improved, no doubt (contrast, namely). Though I haven’t looked at Empire closely yet, and I suppose Jedi looks a bit desaturated. I’ve mostly examined and compared ANH, which looks decent color-wise, on the 1080p disc.
Of course, you’re right that the best purpose these will serve is as a source for future work. Nothing resembling the clipped magenta catastrophes.