If you didn’t notie, the chiefs did not stand other than at obviously non-political comments, like thanking our troops for the heavy lifting hey do, etc.
It is protocol for the military in uniform/on “duty” to not acknowledge politics period. We are all appointed to office by the POTUS (confirmed by the congress) or via authority (in the case of enlisted) by officers so empowered.
Best;
And yes, you are correct in your statement that the military brass in attendance do not display approval or disapproval of any policy, especially military policy.