It’s a review of one author’s theory, but of definite interest to the current administration. The OPR has not ruled out a full investigation; rather, this event is a preliminary review toward one. The above article is a rehash of a Wall Street Journal article that goes into it further:

For nearly two years, the Justice Department has made it a priority to investigate people who previously investigated President Trump. Now it is reaching back in history to consider whether prosecutors mistreated an earlier Republican president: Richard Nixon.

The department is reviewing whether the special prosecutor’s office that investigated the famed Watergate break-in committed misconduct, according to people familiar with the matter, more than half a century after that scandal led to Nixon’s resignation.

Nixon’s tenure has been of growing interest to Trump, Vance and the larger conservative movement. Trump has asked former Nixon aides on several occasions why Nixon resigned rather than fight it out.

The basis of the whole thing is that an author is convinced that in 1972 the DoJ failed in its due process obligations to the Watergate defendants, has written several books that are appealing to the Trump administration, and has now been specifically invited by the DoJ to informally present his case again (emphasis mine):

In 2022, the Justice Department under the Biden administration rebuffed Shepard’s request for an investigation, citing the many years that have passed since the events in question. Current officials wanted to hear him out, the people familiar with the matter said. The review is preliminary, and it isn’t clear whether it will lead to a full-fledged probe, the people said.

Note: The WSJ article is brief and well worth reading, but it is behind a hard paywall. I found an archive link but there are known problems with the site. It has the content; use at your own discretion:

Archive link: https://archive.ph/asff3