...because when Trump was president he accidently/intentionally spilled classified information several times, to the Russians, Israelis, to the media. On one of the occasions that Trump idiotically revealed a classified program the New York Times filed a FOIA request because Trump's mistake, they felt, had declassified the program. Trump's own Justice Department argued against this and won and so everybody in the Trump administration knew a president can't just declassify something without going through the steps required to do so:
The Trump DOJ pushed back on this, however, and successfully argued that mere presidential proclamations are insufficient to formally declassify documents.
"The Times cites no authority that stands for the proposition that the President can inadvertently declassify information and we are aware of none," wrote the Second Circuit U.S. Court of Appeals in its decision against the Times. "Because declassification, even by the President, must follow established procedures, that argument fails."
