If the original version of a movie were still available and accessible, I wouldn't mind if its copyright holders created a new, bowdlerized, "palatable" version that was available along with the original. However, that's not what tends to happen. The heirs of old cultural products often make them unavailable in their original form, depriving modern audiences of the original work. This is a side effect of copyright law which I consider to be a detestable, culture-destroying bug.
I'm glad that no one can censor ancient works that are now under public domain. No one can force us to only read less-scandalous versions of Greek mythology or Shakespeare. But most works made over the last century are unfortunately held hostage to excessively long copyright terms, making them vulnerable to extinction when there is a cultural generational change and the new generation decides to disfigure them or wipe them out. In this way we lose access to cultural artifacts that show us what people thought at the time, for better or worse. Sometimes we even lose access to certain ideas that were better that current ones. Societal progress is not necessarily monotonic.
I'm not saying that I approve of all the values present in old works of art. But I nonetheless want to be able to see, hear, or read such works in their original, unvarnished form. I don't want condescending, contemporary censors to look down on me and assume I won't be able to tell what's problematic in old works or will absorb and embrace values that have turned out to be wrong.
When Spielberg edited E.T. to replace guns with walkie-talkies, was that censorship? Or freedom of speech?
"Sensitivity readings" is hardly a recent concept. The Hardy Boy's were updated to remove the original depictions of racial stereotypes. Was that censorship? Or a desire to make more money?
The 1981 revised edition of "How to Win Friends and Influence People" were edited with edits for "modern sensibilities", including reducing sexist language [1]. Was that censorship?
When is the copyright owner and/or licensee morally obliged to not make legally allowed changes?
Only when the change can be seen as "politically correct"?
[1] For examples, "insurance man" was replaced with "insurance agent", and "leadership gravitates to the man who can talk" changed to "leadership gravitates to the person who can talk". It also dropped the section on marriage. ("Never get married until you have kissed the Blarney Stone. Praising a woman before marriage is a matter of inclination. But praising one after you marry her is a matter of necessity — and personal safety.")
“Speaking for myself, you know, I tried [modifying a film] once and I lived to regret it. Not because of fan outrage, but simply because I was disappointed in myself. I was overly sensitive to some of the criticism ET got from parent groups when it was first released in '82 having to do with Eliot saying "Penis Breath" or the guns...and then there were certain brilliant, but rough around the edges close ups of ET that I always felt, if technology ever evolves to the point where I can do some facial enhancement for ET, I'd like to. So I did an ET pass for like the third release of the movie and it was okay for a while, but then I realized that what I had done was I had robbed the people who loved ET of their memories of ET. And I regretted that.”
If you're worried about overreach of government control, i.e. what these books are actually about, there's a nice thread about Edward Snowden also currently on the front page. Apple, Criterion Collection, etc., have relatively little control over our day to day lives.
I disagree that those books are only about government control. Censorship can come from anyone who controls the distribution of information, and these books are still relevant when talking about the consequences of censorship.