“We’ve almost got some of their telecommunications cracked; the front end even runs on a laptop!” The Mac that sunk a thousand ships could have been merely clunky product placement, not a bafflingly stupid tech-on-film moment.
“Senator Amidala is in a coma. Even if she recovers, she will never be the same and may not live long.” But no… George had to have his god-damned funeral scene, even if it demanded Simone Biles levels of mental gymnastics to save Carrie Fisher’s most emotionally resonant moment from ROTJ, as well as one of the more intriguing OT lore dumps.
Bonus points if a scene was scripted or filmed and got cut.
Kinda the inverse of your question (or an example of this being done poorly) but in the latest or (second to latest) star wars, after being accused of recycling the old trilogy plot over again, the writers attempted to deflect away from the obvious similarities to Hoth by having one of the characters taste what appeared to be snow on a frigid planet resembling Hoth by exclaiming “It’s salt”
“They fly now” is a similarly atrocious example given that they’ve been flying for decades, just not in any of the main trilogy movies yet.