KIMIKO

He's pretty harsh and authoritative when talking to others, then occasionally he will be softer, but no less cold or stoic. He rarely shows outward care or even smiles. Most consistently he does this by making sure his team is physically ok, and they know that that's his way of looking out for them, but he's a pretty closed off person.

Yes, he has incredible amounts of empathy, and yes, he cares deeply for others, but he has to balance this with being Capo and leader of a small team in the mafia where everyone has signed up to die young under his responsability. I'm not sure he can afford being soft and outwardly caring, that would probably destroy him.

He's also just... a lowkey person, in general. He's very sociable and conversational, which he got from his mom, but even as a kid (from what little we saw) he seemed quiet and pretty expresionles (really reminiscent of Giorno to me), which he probably got from his dad, a kind man who regardless didn't express many emotions.

TLDR All of his kindness, empathy, and care is filtered through stoicism and how the mafia reinforced his coldness. He rarely shows outward care but he's often portraited in fandom as a very open person, therapist or mom like, when I think that's very far from how he was written.

...And as an extra, I absolutely think this is also a side effect of male socialization. It's so interesting to me that despite Narancia being so open with his own emotions, it's Trish, the only girl in the group, the one who thinks Bruno is too cold towards them, while Narancia sees care through the stoicism and the scolding. They all find it normal, maybe even reasuring, because it's what they've all been raised seeing in other men, especially Narancia with his own dad.