Well, there's our explanation for why Kunishige was so sloppy. Likely started off as a symptom of what was essentially depression/apathy, plus a disregard for his own wellbeing - which perhaps just became an unfortunate tendency for him (and I don't doubt he 'relapsed' after Akemura's actions).
I think this chapter also gives us some important context for why Kunishige ends up holding the principles he does regarding the creation of swords.
When Ch. 122 came out with Kunishige explaining his views to Subaru, I think a lot of folks opted to be pithy about it ("just stop making them bozo" etc. etc.) rather than consider the context of Kunishige's life and the themes of the story.
This is boy who's grown up in a society fraught with senseless and near-unavoidable violence, where the people who should be doing something about - the government/the Soga clan - are barely holding on.
No doubt, he's grown up hearing stories of wandering heroes - Samura, Ibuki, and the like - people who wield their blades in service of the common folk. He sees his friends - the people who gave him a reason to keep going despite the trauma he's endured because of his gift - and wonders what he could do to keep them safe.
He's not talented with sorcery like Shiba, or physically powerful like Azami. He lacks the family connections of Chiaki, or later her political importance. All he has are his eyes, and the knowledge of how to make weapons.
And so, he commits himself to the forge. But he's not like the other swordsmiths, the ones who strive for accolades from the nation, or excellence for the sake of itself - he's seen the ugliness behind the craft, even to those who are barely connected to it.
And so he takes care to only give his swords to those he deems worthy - those who would use their power for the sake of protecting people like the boy he used to be, the kid who had nobody but his friends to rely on.
This is hardly a unique theme, mind you - who gets to wield power, how should it be wielded, should it be wielded at all... those are very common themes in fiction; Kagurabachi just touches on it specifically in the context of weapons.
Could Kunishige help by making something other than swords? Maybe... I'm skeptical myself. But it would mean training to make things he's not familiar with, things that may not help his friends as quickly as he wants.
But a sword? He knows how to make that.
