Assuming copyright laws don’t change by then, otherwise there is no way to know.
A plausible answer is 1977 (when the film was released as Star Wars) + 95 years (for pre-1978 works) = after 2072. However, the film had been edited by George Lucas for the 1997 “Special Edition” release. Does this mean that I cannot publicly play the Special Edition VHS tape I have at home in 2073 and have to wait until 2093, or perhaps 70 years after GL’s death?
George Lucas has been infamously attempting to erase copies of the original movie. Therefore, no HD home video release for the 1977 film exists, however, a fan effort known as the “Despecialized Edition” compiled different versions of the movie from various sources, patching the Special Edition 4K Blu-ray rip to try to replicate the original 1977 experience. Does this legally questionable version enter public domain in 2072, or does this only apply to official (SD) releases?
Anyway, the Despecialized Edition project as well as George Lucas’s treatment of the originals is an interesting rabbit hole to delve into for any movie nerd.
The way things work with Sherlock Holmes, some of the original novels are in the public domain (because they were written before the cutoff) and and others are not (because they were written after the cutoff.)
Sherlock himself is in the public domain. And he plays the violin. That’s also in the public domain. But he didn’t get a dog until a later book, so that’s still under copyright. And he didn’t get a diagnosis of bipolar/manic depression until later, so that’s also under copyright.
So if you want to write a book about Sherlock, that’s fine just as long as you don’t give him a dog or bipolar or otherwise use any elements from after the cutoff.
So, I believe the original trilogy will be in the public domain in 2073 and later additions (Han shooting second, musical numbers added to the special edition, etc) won’t be in the public domain until later.
If the “Despecialized Edition” was made from the 4K version, I think it’s certain that the elements added after the original trilogy’s release would be remain under copyright for a time after 2073. But if there are any scenes that are straight up one-to-one identical between the original release and the 4K edition, I’d guess whether those would be under copyright after 2073 would depend on whether restoration and/or upscaling qualifies as sufficiently “creative” to warrant it being a distinct copyrightable work from the original release version.
Now, even just the act of making copies of parts/all of either the original or 4K endition (in the process of making the Despecialized Edition) probably qualifes as copyright infringement. So those folks definitely would be in trouble if Disney went after them. But after 2073, whether trading copies of the Despecialized Edition will be illegal will depend on whether upscaling and restoring qualifies it for fresh copyright, and also whether any copyrightable creative elements from after the original release are included in the Despecialized Edition.
Sorry. That’s a lot of words just to say “I dunno.” But I think it’s fair to say that after 2073 if someone upscaled the original theatrical version from that DVD release that had it (assuming nothing new was added to that not in the original theatrical release), it’d be perfectly legal to create and trade copies of.
I think that at least the sub-title “Episode IV: A New Hope” was added in that DVD release… Anyway, a “4K77” scan of a 1977 film reel distributed directly by the studio exists, it’s just noisy and needed color correction.