The officers do not want a boss who is giving illegal orders while scapegoating the generals and soldiers who follow them:

At the White House on Monday, Karoline Leavitt, the press secretary, read a statement that said Mr. Hegseth had authorized the Special Operations commander overseeing the attack, Adm. Frank M. Bradley, "to conduct these kinetic strikes."

She said that Admiral Bradley had "worked well within his authority and the law directing the engagement to ensure the boat was destroyed and the threat to the United States of America was eliminated."

Bradly gets pushed forward to take the beating while Hegseth and Trump claim innocence:

Bradley will have the chance to address outstanding issues about the strikes when he speaks with lawmakers Thursday behind closed doors. Some lawmakers have said the Trump administration appears to be making Bradley into something of a scapegoat.

"Looks like they're throwing him under the bus," said Sen. Rand Paul (R., Ky.), often a critic of the administration, "but these kinds of decisions go all the way to the top."

Adm. Bradley had the poor choice of following an illegal order or getting fired.

In my recent piece abut U.S. strikes on boats in the Caribbean I suggested that the head of Southern Command, Adm. Alvin Holsey, was made to retire because he rejected orders to kill survivors of U.S attacks:

On the very same day those survivors were rescued, October 16, the DoD announced that the head of its Southern Command was 'stepping down': ..
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It now seems clear that Admiral Holsey got fired for not following Hegseth's illegal order and for ordering the rescue of the survivors of the strike.

A piece in today's Wall Street Journal confirms this impression:

Defense Secretary Pete Hegseth shocked official Washington in mid-October when he announced that the four-star head of U.S. military operations in the Caribbean was retiring less than a year into his tenure.

But according to two Pentagon officials, Hegseth asked Adm. Alvin Holsey to step down, a de facto ouster that was the culmination of months of discord between Hegseth and the officer. It began days after President Trump's inauguration in January and intensified months later when Holsey had initial concerns about the legality of lethal strikes on alleged drug boats in the Caribbean, according to former officials aware of the discussions.