I felt like “shadiest” was hyperbole meant to mean “very shady”. Also while the others mentioned might be bad, the NSA is probably the “best” at being covert an

I felt like “shadiest” was hyperbole meant to mean “very shady”. Also while the others mentioned might be bad, the NSA is probably the “best” at being covert and probably the most active of all of them. So they might truly be the “shadiest” by sheer volume of covert things they do.