The insidious message had two major aspects: It was FACTUALLY correct, and it was intended to cause members of the Armed Forces to question their orders. There could be no other purpose.
Imagine handing out a flier to public school children telling them that Education majors in college have the lowest SAT scores of any college degree. It's factually true, but its purpose would be to foment disrespect and ridicule of teachers - put them on the defensive for no legitimate reason.
The recent communication is analogous to the infamous letter by the 51 national security professionals, stating that the Hunter Biden Laptop story had all the earmarks of Russian disinformation. It was factually true, but intended to mislead and create the false belief that the felonious activity documented on the laptop was somehow compromised, when it wasn't. And the signers of the letter knew it wasn't.
The Left is evil.