gintoki, if anything, should hate bakufu more than any of the joui4, but he doesn't aim to overthrow them, gintoki's goal is to protect what he cares about and he's willing to throw everything away to not avenge but to protect the soul of shoyo and what's been etched into him

after the war gintoki was empty and lived like so because he didn't want to lose anyone, he could've aimed to overthrow the bakufu like zura or takasugi, but he places his need to protect over anything else, gintoki never fought bc he didn't like bakufu, he fought to protect

like gintoki is such an admirable character?? he doesn't have an overarching goal because why does he need a goal to reach when everything he's wanted is right in front of him and got there before he even realized it?

he realized it's useless to avenge the past, but he knows the value of the present and wants to protect what was given to him. gintoki feels that the sins he carries makes him undeserving of the bonds he's made that's why he'll do anything to protect them

like he's not necessarily driven by ambition, he's not seeking approval or anything of that sort, but he still does everything he can for the bonds he's created, he throws everything on the line for people he's come to care for and know are good people

he's felt pain and he's knows what it means to bear a burden heavier than any planet in the universe and he knows what it feels like to lose to your own weakness. gintoki knows these feelings all too well,

and he makes it his duty to throw everything on the line to never have anyone feel that or to lose anyone because he can't lose what's he's been given, he can't live through that again and won't let anyone else do so either

tl;dr gintoki is such a well written character without a lot of things being clear cut, there's so many layers and nuances. truly, masterfully written