I believe Judge Cannon has already questioned Jack Smith as to whether any other President has ever been charged under the Espionage Act, and I think she mentioned Joe Biden. This is definitely on her radar.
On a side note, a recent case before the U.S. Supreme Ct. alleging selective prosecution by local police has drawn a lot of interest from the Justices. From what was reported, the Supreme Court is aware of the issue. There was a lot of questions by some of the Justices. The liberal Justices were actually pretty critical of the police for engaging in selective prosecution.
I would not dismiss the legal weight of it, though. The “selective prosecution” argument reinforces — almost perfectly — the questions that were asked by several U.S. Supreme Court justices in one of the J6 cases before them right now.