Everything you said in your post is exactly backwards. The Earth 2 news outlets you read (and Trump) are lying to you.

From the linked AP article:

"THE FACTS: That’s a flagrant misreading of the law, legal experts say.

The law, which took effect in 1981, requires the preservation of White House documents as property of the U.S. government.

Jason R. Baron, a former director of litigation at the National Archives and Records Administration, said that the notion that a president could declare any record as personal goes against the “very reason” the law was created. NARA is the federal record-keeper and the agency that repeatedly sought the documents kept by Trump.

Congress passed the act in 1978 in the aftermath of the Watergate scandal, when a collection of secret tapes that President Richard Nixon had considered destroying played a defining role.

The law, he and other experts note, clearly distinguishes between “presidential records” and “personal records.”

“The definition of ‘personal records’ is narrow, clear, and functional: it includes only records of a ‘purely private or nonpublic character’,” Peter Margulies, a professor at Roger Williams University’s School of Law in Bristol, Rhode Island, wrote in an email. “Any record that touches on information relevant to presidential decisions on foreign policy or national security is a presidential record. Period, end of story.”

Josh Chafetz, a professor at Georgetown Law, agreed, saying there’s “simply no way” the records described in the indictment against Trump could be considered “personal” under the act’s definitions.

Among the documents found at Mar-a-Lago were ones marked “SECRET” or “TOP SECRET.” The documents included details about the country’s nuclear weapons and the nuclear capabilities and military activities of other countries. Prosecutors allege, for example, that Trump showed off a classified map of a foreign country while discussing a military operation.

“There is no way to read that statutory language as giving the president ‘discretion’ to categorize military plans, to take just one example, as ‘personal’,” Chafetz wrote in an email."