I can’t prove it, but I swore I read when George Lucas sold his company to Disney, not releasing the original cuts was a condition.
Maybe that’s true, but there was an expiration on it. Dunno.
It stems from people at LFL being cagey about it for so long. Kennedy, Hidalgo, made weird comments when asked after the Disney sale so people naturally assumed they’d got a contractual reason behind the scenes. Unless this has recently changed or they were just saying this for personal rather than legal reasons to stay friends with George.