I've watched a bunch of clips from this. And, I sort of wonder if the message was not for the actual audience of flag officers, but the general public. I mean, the generals and admirals know what's what. They know Trump's bullshit about Biden, the state of the military before he became president, and the reasons why they have things like shaving exemptions and so on. They know what the military's strengths and weakness are, and it is very likely that neither Kegseth or Trump came close to addressing them.
And, the flag officer's silence spoke volumes. It could be interpreted that they were being stoic, not outwardly disagreeing with the commander in chief or secretary of defence. We can never really know what they think...but...
Here's the thing: All Generals are university educated. Most, if not all, have advanced degrees (MA's, PhD's, etc.). They didn't climb the ranks just because they were good looking or ass kissers (though that could have helped). They also know the rules of military justice and have all sworn to protect the constitution. The majority of these guys probably went to West Point, Annapolis of the Air Force Academy, where there are mandatory courses on leadership and following the law when it comes to acting on orders. Now, I'm not saying there isn't likely a few MAGA morons in the mix here, but by and large, they don't serve Trump per se, they serve the constitution. I expect that if Trump orders them to attack Americans on American soil, odds are they will not follow those illegal orders and push back. Or resign in mass. Honour is a big thing for most, if not all, of them.