this is really obvious and well laid out in the manga, but i just really like the way that all might and bakugou's final fights both center around closure for the things they said to izuku in chapter 1. and both of those fights are clearly a culmination of multi-faceted character arcs for both characters, but i still find it really interesting that the centerpiece for those fights is the way that they are both forced to confront, one more time, the incorrect things they told izuku in chapter fucking one.

All Might in chapter 1 tells Izuku that quirkless people can't be heroes. Even in chapter 1, we can see how this statement is almost as much about him and his own anxieties about his limitations as it is about Izuku. And that's expanded on in his character arc throughout the series, which focuses on power and powerlessness as he gives up his quirk and has to figure out how he fits into the world as a quirkless person. And here in the end, we see repeated flashbacks to that first conversation on the rooftop as he fights all for one quirkless, despite tsukauchi telling him he can't do it without a quirk.

Other things in that final fight act as culminations of his character development--All Might, once a pretty bad teacher, using support equipment that showcases the quirks of the students he's come to love; All Might, who spent so much of the series with the expectation that he would sacrifice both his body and his life to heroism, instead surviving the fight because he wanted to live. But the clear central theme of the fight was All Might, experiencing the powerlessness he once saw in Izuku, and being a hero in spite of that perceived powerlessness (the same way he saw izuku step up that afternoon).

Like All Might's fight, there are many culminating themes in Bakugou's fights with Shigaraki and All for One--the boy who viewed himself as All Might's end getting to save his hero, the boy who was once left to die in the hands of a sludge villain brought back to life by a new trio of heroes (that was a point someone else made, link me the post if you can find it because I sure can't).

But the central theme in that fight is clearly tied to his words in chapter 1, when he tells Izuku how worthless he is, tells everyone else in his class that they're just secondary characters in his story, and notably tells izuku to kill himself if he wants to have a quirk (wants to be worthy) so bad.

So then! Of course! In his fight with Shigaraki, Shigaraki tells him that he's worth nothing outside of who he is to izuku, basically calls him a supporting character in somebody else's story. And then! Bakugou walks back into the fight, knowing he's gonna die, and his last thoughts are if he will ever reach izuku (will he be worthy?).

And like. Then he comes back to life, accepts izuku's hand, accepts help from all might, says a sincere thank you to edgeshot, says, 'this is our tale!' and 'i'm the guy that steps in when the nerd can't handle it on his own!' and 'yeah i never coulda hoped to beat that, at least not alone.' because he's not the only character in the story, but that doesn't mean that he's weak or worthless. and, just like all might, at the culmination of bakugou's fight, we get the flashback to chapter 1 izuku, and bakugou changing his answer to izuku:

anyway, people have talked all this to death but i just! really really like the way that these fights bring everything back to the beginning of the whole story, the way they turn the words that both characters spoke to izuku back on themselves, and the way that they both answer the 'original sins' of bakugou and all might, and showcase just how much both characters have grown and developed over the course of the series. it's just. so well done!