Why is it ROTJ PDE always and i mean ALWAYS looks hugely better than the other PDE versions in my opinion? My answer: I think it's because ROTJ 2004SE is such a shoddy version that any improvments are going to look great. For one, the colour looks about 100x better in that recent clip.
(No disrepect to the other PDE versions by the way - just I see the improvments more in ROTJ because I really disliek the 2004 SE of this film much more than the rest).