You have to understand the CIA's point of view

Trump released a memo on Thursday explaining why he had decided to block — at least temporarily — the release of some files.

[...]

He added that some executive departments and agencies had proposed that certain information should remain redacted "because of national security, law enforcement, and foreign affairs concerns."

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The law, which mandated the release of all documents related to Kennedy’s assassination, was signed by then-President George H.W. Bush in response to “JFK,” the conspiracy-filled Oscar-winning movie from Oliver Stone that had been released a year earlier. The law ordered the immediate release of thousands of pages of documents and set the 25-year deadline for the release of the 3,100 yet-unseen documents as well as the full, unredacted versions of the 30,000 pages already made public.

  Politico

Obviously, the CIA is above the law.

Trump said that all the information in the redacted documents will be withheld from the public until no later than April 26 of next year, and that agencies will have to propose any further postponements by March 12.

At which time, they'll just come up with another "national security" reason not to release them.

While many of the documents released Thursday were created in the 1960s and 70s, a small number of them — mostly sourced from the CIA — are as recent as from the 1990s. Such documents could have the potential to expose relatively recent intelligence and law enforcement operations.

Let me guess: when the law was created in '92, the CIA immediately set about creating a bank of "new" information with some not-necessarily-related current intelligence that they could point to as making the trove of documents too recent to be released. Nobody was still investigating the assassination in the 90s. Well, nobody in the government. Or the CIA. The CIA already knew what really happened in the 60s.

Maybe they're busy right now creating more documents with current intelligence in them to stuff the files.

Following the White House's rollout, researchers expressed skepticism that the CIA and FBI didn’t have enough time to fully review the files for any information that might still risk revealing intelligence sources and methods.

"I guess nobody had 25 years to prepare for today,” said Rex Bradford, president of the Mary Ferrell Foundation, a nonprofit research organization that has digitized hundreds of thousands of documents and government reports about the Kennedy assassination.

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“This is a fiasco,” said John McAdams, a political science professor at Marquette University and JFK researcher. “These issues should have been resolve weeks, if not months, ago.”

Again, if you were in charge at CIA and you wanted to keep some things from being publicized, you would not have attempted to resolve any issues.

 ...but hey, do what you want...you will anyway.