TPM and AOTC got hit with DNR before the DVD releases.
They both also got the colors and contrast muted for TPM for a lot of nice scenes and colors and contrast got muted and the colors a bit shifted for AOTC.
AOTC also never a home release to match the 35mm theatrical release, the home releases are all closer to the digital theatrical release (which oddly looked a bit duller to me than the 35mm theatrical releases even though the TPM digital theatrical release was even more intense than the 35mm theatrical release).
In the end, the UHD brought back the contrast and some of the color for some key scenes so, once max brightness is dialed down, it looks closest in those regards to the original theatrical releases and improves a lot on prior home releases. Still has the DNR though and a few things still seem less saturated.
The AOTC UHD, for some reason, didn’t seem to bring the pop back that, at the least, the 35mm theatrical release had and it looks a bit flat and muted and the colors also are still shifted and it’s also DNR’ed. The HDTV version from way back and overseas is closer.