Making people rich and powerful wins their hearts and minds pretty fast.
Look up the military leaders of the USA. Secretary of Defense, Chairman of the Joint Chiefs of Staff, Service Chiefs (Army, Navy, Air Force, Marine Corps, Space Force) ... all appointed by Trump.
You've gotten inaccurate information. Only the Secretary of Defense and Navy chief were appointed by Trump, the rest were appointed by Biden. (The incoming chairman will also be a Trump appointee, of course.)
The seat is formally unfilled, so the vice chairman Christopher Grady (appointed by Biden) is the current acting chairman. You may be thinking of Dan Caine, who Trump nominated for the position but hasn't yet been confirmed.
Look up the military leaders of the USA. Secretary of Defense, Chairman of the Joint Chiefs of Staff, Service Chiefs (Army, Navy, Air Force, Marine Corps, Space Force) ... all appointed by Trump.