and lucas was heavily criticized for comtradicting himself. does that excuse other creators contradicting some stuff that came before? imo no it doesn’t.
In my mind it all comes down to what services the story. Vader as Luke’s father is a retcon but also one of the most powerful developments in the saga (and cinema history, really). Luke and Leia as siblings isn’t awful but doesn’t ultimately have much bearing on ROTJ. Padme dying in ROTS contradicts a line in the OT but in my opinion is absolutely essential to the story that ROTS is telling, and the movie would be worse without it.
Basically, it depends. Many fans are binary about these things. I don’t think that’s the right way to go about it.