The indictment is obviously a hit piece on Trump, when this likely could have been negotiated away. One of the best precedents in his favor are the tape recordings Bill Clinton made of his phone calls with foreign leaders, which he was ultimately allowed to keep, when he was taken to trial for keeping them.
However, the biggest question to many in court of public opinion, is why did/does Trump think he needs to keep these classified documents, such as potential war plans, in his possession in the first place?
For one, the military is now being run by The Woke. Should Trump regain power, it might be convenient to have plans, actually written by military leaders, just in case they are needed.