OK, and? He can drop that suit at any time and it will stop there, but such a lawsuit is a useful tactic. Specifically, it's a MAD tactic, because he knows he is also implicated (I don't think anyone genuinely believes he's totally clean on the Epstein stuff) and the GOP broadly and Trump in particular want to go after the Clintons in particular.

If he was genuinely about transparency, why do you think he fought and delayed on the subpoena until Congress moved to find in in contempt of Congress? The purpose of such a lawsuit is to create a threat against them to protect himself by threat of mutual destruction. Same as pushing for any deposition from the subpoena being totally public - also about mutually assured destruction. The goal is to threaten that if the Clintons are gone after in a serious way, he'll take them with him.