It's a personality thing & not an "Admirals thing".
Greenbull comes to Wano - tells everyone that racism/classism is what allows the World to work & that he believes they have no Human Rights. Literally the shit you see in the Real World right now.
Akainu nukes the entirety of Ohara to make sure not a single Scholar escaped.
You guys love to romanticize that - "Akainu did Nothing Wrong".
Then complain when people like Greenbull & Akainu are called trash for siding with Philosophy that is Trash.
Heck slander an extremist like Sengoku too - his entire Speech to begin the War at Marineford involved around we're Publicly Executing you because you might become another Roger. Completely dehumanizing Ace.
People like Aokiji, Fujitora, Garp are an exception.
Fujitora & Aokiji reasons are Obvious.
Kizaru too believes he is just another "Cog in the Machine".
Garp? He is literally a Marine Luffy.
He is what Luffy would've become had he not met Shanks but a Marine instead & had a single bad experience with Pirates.
He is canonically the "Freest Marine in the Sea" just like how Luffy wants to be the "Freest Man in the Sea".
He is simply fighting for the Greater Good, his entire story in Marineford was whether he'd sacrifice his Grandson for the Greater Good.