Dabi is going to die and Iida will risk his life to save Shoto.
First of all, I have to point out that Dabi is essentially unforgivable (don't come at me, I have a point). I don't mean this from a moral standpoint, but a narrative one. This to say I don't think Dabi is beyond redemption and deserves to suffer for his actions, what I'm saying here is that I don't think his character can be redeemed within the BNHA narrative. So, he either lives and some sort of redemption arc is hinted to signify that no one is beyond hope in this new society our young heroes are building (if this is the case he will be part of the Tordoroki dinning scene in some capacity), or he will die. Lately I believe he's not going to make it, tbh.
It all comes down to the one capital sin for BNHA: inaction in the face of suffering.
So let's start from the beginning. Izuku might still be trying to become the greatest, but he became a hero since episode one. Because when he saw someone suffering he didn't even think about it, his body simply moved on it's own. Our protagonist can't stand still just witnessing someone else's pain, he moves instinctively, he acts.
This isn't simply a facet of Izuku's character, it's his very essence. The first time we see him he's defending a weeping kid, when he first tapped into OFA consciousness he didn't even have a body, but watching Tenko cry made him charge forward. He wants to help the crying little boy every time, he can't help it.
Sometimes that behavior is self-destructive, reckless and even irresponsible. People around him have tried to make him stop and give him a hard time of jumping without thinking. But the only time he didn't act the narrative chastised him for it. He let Eri go with Chisaki, and even tho his teacher told him he did the right thing and his inaction was understandable, logical even, it was latter framed as a terrible mistake.
Mirio, following Nighteye's instructions, convinced him to let her go. By the end of the arc one lost his quirk and the other his life. Izuku only survived himself because he succeeded in saving Eri, if he would've failed to save her a second time, he would've died. Mirio only got his quirk back after he helped Eri recover and smile again.
All this to say, inaction, even when logical on even justifiable, is unacceptable in BNHA.
Regardless of what could be said about that particular brand of heroism, that's what the story is selling. Heroism is (among other things) sacrificing yourself for the sake of others. And it's not exclusive to "heroes" either, villains too have sacrificed themselves to save others, Mr. Compress and Twice being the most memorable examples.
Enter Dabi. Going a mile a minute in the opposite direction.
After waking up from his coma he goes back home and he sees for himself Endeavor's continuous and relentless abuse.
We know Shoto's probably crying there, he might've thrown up at this point, we've seen it happen before from his memories, but here we don't get a close up. Shoto is part of the background because Dabi didn't spare him a second thought, he didn't care for his brother's suffering, only his own. Shoto is in pain, but Dabi's obsession with Endeavor is so great that he can only see the eyes of the abuser and never turns to see his own brother how's hurting right before him.
A lot of characters have failed to save someone in the series, but they've failed because they either couldn't reach them in time, they weren't strong/fast enough, they were so terrified they froze, or the laws/their superiors prevented them from intervening. Dabi didn't have any of this barriers, he had the table set for becoming a hero himself. He was standing right there in the door frame, unafraid, but so incredibly angry and self absorbed that he couldn't look beyond how that scene affected him.
He saw someone in pain and did absolutely nothing to help, what's more, he didn't even notice. In that moment he could've stepped in (literally), he could've become his brother's hero, but instead he decided to turn his back. He focused solely on his hatred for the abuser and completely disregarded the victim. And that goes fundamentally against the entire premise of BNHA
*sighs*
Enter Iida. Because… well, he did all that too, didn't he?
In Hosu City he ditched his internship during an emergency and went after the Hero Killer instead. He was right there in the alleyway, and he did absolutely nothing to help the injured hero, what's more, he didn't even notice him. He focused on his hatred for Stain, and in doing so disregarded the victim completely. It wasn't until Stain pointed it out and he saw Izuku and Shoto risking their lives to save them both that he finally snapped out of it.
He was injured and ashamed and still he admitted he was in the wrong, he took a stand, he got stabbed twice saving Shoto, he stopped Stain (with Izuku's help), he accepted the consequences without complaint, he asked for forgiveness and still the narrative punished him for what he did. He got permanent damage on his left hand and refused to get treatment until he makes up for his faults. Until he becomes a hero.
So... they're two sides of the same coin. The only difference is that Iida recognized what he did as a mistake and wants to do better. I think the story is about to give him the chance to become the hero he wants to be. The only question is what price will he pay for it.
_ _ _
When the teams got divided at the beginning of this final battle I was wondering why was Iida on team Nomus/Dabi. His power is not particularly well suited for withstanding extreme heat (or extreme cold, for that matter), it seams like Inasa would've been a better option to assist Shoto against Dabi's flames. Iida couldn't even provide support during the battle.
So why is he there?
Because there's a glowing spot in Dabi's chest and I don't think it's the beginning of some sort of regeneration. It's a bomb. Maybe it's one of OFA's fail-safes and he will ultimately survive, or it's Dabi's own power and he will die by his own hand like he wanted, but it will certainly go boom. And when it does, the only one fast enough to get injured Shoto out of there in time
Is the class president.