Compare & contrast with the multi-million dollar fines given to the bankers sending work-related texts via IM like WApp/Signal…
All in all, not a _great_ position for his lawyers to be in, tho. “Our client is really incompetent, so probably did all sorts of illegal stuff with DMs, and executive privilege might apply to some of them” is a hell of an argument to have to make (I mean I doubt they came right out and highlighted the “this would generally be illegal” angle, but it’s implied).