You are "desperately fishing" by interleaving two different things, the presidential
classification of documents and the post-presidency
possession of documents. I'm stating the constitutional defense basis for presidential classification, and not arguing or defending the post-presidency possession. Your emotional response re: Trump's suitability for office is immaterial to this argument; please recompose and focus on the argument.
Then you can understand my references to his Jan 19, 2021 are concerned solely with the orderly declassifying of Russia investigation documents:
Memorandum on Declassification of Certain Materials Related to the FBI’s Crossfire Hurricane Investigation – The White House Here's background on it:
Final Trump declassification request to DOJ blocked after he left White House - and how FBI/DOJ has concealed its malevolence for six years now. Meadows convinced Trump to orderly declassify the documents.
To boil your position down, you predicate
the vested authority of classification itself upon whether or not the president follows bureaucratic procedure or custom; the constitution establishes no such predication, and the court has been mute except to convey singular authority.
Again, whose procedures must the president follow to declassify? Where does the constitution subject that authority to procedural underlings? Or statutes of Congress, for that matter? You should re-read the last link I gave you.
I'd share a cell with Bubba because I'm not president. Neither were senior aide Sandy Berger or SoS Hillary Clinton but rather subordinate officers who mishandled, misappropriated, stole, and destroyed classified and otherwise official documents. See the analogy fail?
Perhaps you'd rather focus on the argument of records possession, declassified or not, instead of classification - ? You have some defensible positions there.