I don’t understand how the government uses copyright to censor anything. By law, the federal government cannot prohibit copying its works. Other levels of government are usually required to make available public records, so for example they cannot suppress dissent by forbidding discussion of a particular law (anyhow, that right is covered by the First Amendment, which trumps copyright law). A state or municipal government could, for example, publish a book and under copyright law could forbid you from copying that work, but I don’t see how that constitutes censorship. That’s a point that needs to be explained.
It is not censorship when a publisher exercises its property right to a work that it owns. Censorship is an act done by the government
Your implication that copyright expiry is not “readily available” anymore is simply untrue – copyright always expires at a legally-defined time. Maybe you are claiming that the duration of copyright is too long. The 75 years vs. 50 years vs. 25 years question is a difficult one, but “arbitrary” numbers are necessary in a society with objective laws. The determination that a person can be held liable for contracts at age 18 is an “arbitrary” number, perhaps the number should be 19 or 17. If you want to argue that a 4 year old should be held liable for their contracts, perhaps that would be an topic worth discussing separately.
And fyi, “fair use” is rampantly available. The main problem with fair use is that it is not clearly defined – what counts as “fair” is highly arbitrary.
Physical copies can disappear at the whim of certain people (“owners”) just as much as electronic copies can. There are tons of physical products that I can’t get anymore because there doesn’t seem to be sufficient market to warrant maintaining the machinery. That’s life.
Far from suppressing the acquisition of desirable stuff, the expansion of electronic means of promulgation has made it much easier to get free stuff. Print books are rather expensive, and electronic books are dirt cheap, or could be. These days, it is not difficult to self-publish and freely distribute a book that you write. An author has to make a choice – do they want to make money from the work and do they want it to be widely and systematically disseminated, or are they satisfied with free, informally-distributed samizdat? If you’re not happy with your particular publisher, there are plenty of competing publishers, so I don’t see how publisher control is relevant to the question of whether I have a property right to the book that I write.
I just don’t see any argument here that government officials have in any way corrupted concepts of intellectual property rights. Your objections seem to be based on commercialization – Disney not making their movies available all the time and using the law (statutory law and the law of supply and demand) as a way of generating value; contract law and the fact that you can’t sell trade secrets when you agree to not sell trade secrets.