#overall though

I have three (four) main points I will go through that are related to Izuku's story that imo were ended well:

One For All & what the quirk did for Izuku & how it ended.

Izuku's on-going career, resulting in him as a teacher.

Izuku's future career with the hero suit.

2 and 3 also both pick up one of MHA's main themes: What it means to be a hero.

So, let me start with One For All (OFA).

OFA is the quirk that kicks off this series because it's the quirk given by the Symbol of Peace All Might to our protagonist Midoriya Izuku, who has been quirkless but dreamt of being a hero. There are a few important things to note about OFA:

OFA is very strong; so strong that All Might, even after agreeing to give Izuku the quirk, makes him train. A lot. And hard. Because a regular body would not be able to handle OFA due to its nature.

We learn later that not only does it cultivate the raw strength of all its previous users, but that it holds their quirks too. And that these quirks got stronger with each generation of OFA user as well.

In fact, the major reason why OFA is so insanely strong when Izuku receives it, is the fact that All Might had been quirkless himself and therefore is the longest holder of OFA as the other users could not handle having their own quirk and OFA as additional one, passing away rather early.

OFA is also the quirk of Yoichi who is All For One's (AFO) brother who, in very simplified terms, have a long history and complicated, but hostile relationship with each other. Yoichi wants to stop his brother.

And, to make a very, over 400 chapters long story short: Izuku defeats All For One and he does so after countless of training and battles where he learned to make the best use of OFA and in the end by transferring OFA to Shigaraki/AFO.

Izuku has always understood OFA as a borrowed power and ultimately as one he'd be the last user of—OFA was a power used to defeat AFO and the fact that transferring it, ultimately what AFO had always desired, is part of what destroys him is very fitting.

OFA has given Izuku the chance to enter the world of heroes—and to help change it in the long run. He was able to open the people's eyes about society, he has shown that even after he gave OFA away, he would still fight and he has animated people to be heroic even if they aren't employed as heroes. He has added more meaning to the word "hero".

Izuku as teacher, part 1 of what it means to be a hero.

Now, I have seen a lot of criticism to Izuku ending up as a teacher and I am here to tell you—it's perfect for him! Izuku is someone who loves learning, he is genuinely enthusiastic about it, and especially about quirks—he loves geeking out about them, he spends his free time analyzing them and drawing out their potential, he is an amazing supporting character for children that need assistance in finding their footing in the world of heroes. Who can you learn better from than from someone who loves learning itself? He's got a contagious kind of excitement that sparks over to you.

And, he knows better than anyone how chasing after this dream of being a hero feels like, knows better than anyone how important people supporting you on the way is—because this is what he has received, back then, when he was in high school himself. Izuku has learned and experienced himself how important support from the people around you is, so he now wants to provide exactly that to the future generation of heroes. He wants to guide them on their path.

This career path also opens a new perspective that MHA has been trying to tell us for so long now: "Hero" isn't just who goes up and picks up this nice certificate and runs around the city with the "hero badge". "Hero" is more than that. Helping people, in any little way, is being heroic and makes you a hero. Teachers are heroes too. Izuku is being a hero, even now that he doesn't do "pro hero" work, because he is helping children—a teacher doesn't only educate, a teacher provides mental support to some extent too, and that goes even moreso for UA and other hero school teachers. Teachers protect their students as well. Izuku is, by all means, still a hero, just not a "pro" hero. He is a guidance to children and is dedicating his life to extend a helping hand to them and their dreams.

And he's happy with it.

Yes, it's also said that he misses the work of a pro hero—but that doesn't mean that what he is doing now is bad or "settling". He could have done SO many other things, but he CHOSE to pursue a career as a teacher—because this, too, is something he enjoys and finds happiness in. Both statements can be true. You can miss something you used to dream of all your life—it's very natural, even, but you can still be happy about where you ended in life right now.

Moreover, even if you don't agree with my take as "teachers" being heroes too, we see just a few panels later Izuku being a hero:

Which further emphasizes the point I and MHA have been trying to make: You can be a hero even if your job title isn't "hero". That's why civilians got statues too, that's why they are considered for the heroes ranking too. You can have a diverging opinion on how effective it is, but that is the point that is being made and the characters in-universe try to bring across too.

The hero suit and the conclusion on what it means to be a hero.

Truthfully, I don't know why people keep acting like MHA ended after Izuku's teacher career, because we have a conclusion that even traces back and argues back against anyone who doesn't agree with my points about him being a teacher and still a hero. And, more importantly, it brings the full manga into a perfect circle:

Because remember what the manga opened with: Can you be a quirkless hero?

And in so many ways across all these 430 chapters, but now even in the most literal sense of itself, MHA is telling you: YES. Yes you can! It shows us that you can be a hero without a quirk because anyone can lend someone freezing or wounded a t-shirt and anyone can reach out their hand to someone who is lost and anyone can sprint to catch a stumbling child.

But, also, our protagonist Midoriya Izuku, who is quirkless and had lived his dream at the age of 15-17 after borrowing a quirk, now is only starting his dream again at the age of 25: He can be a (pro) hero again and that although he doesn't have a quirk.

Yeah, it's expensive and not yet affordable for the average quirkless guy. But that's not the point of the story, because we started with asking "Is it possible at all?" and were first deluded into thinking the answer is "No.", but MHA is here to tell you: Yes, you can be a hero. There is most certainly an argument to made that now that the first one has done it, more might be able to follow in the long run.

So, what does it mean to be a hero?

I think MHA's message on that is: A hero is someone who steps up because they can, who helps people achieve a part of happiness because they have the chance to. You don't have to have a quirk or do grand gestures, you don't have to rely on the "professionals" to take care of it, at least not if you can make a difference already. There is no shame in a little heroic act because it doesn't make the act less heroic. There even is beauty in everyone being a little hero to each other every day.

Some last words about my feelings on MHA's ending.

This isn't really part of the thread anymore, but I still wanted to say this. This is purely personal, but, to me, what was really beautiful was: Midoriya Izuku didn't "peak" in high school, he had one peak in high school, but life is made of multiple "peaks".

Izuku is 25 and hasn't even seen all of the world yet and now he gets to live his dream again. Because you never know where life takes you and even if you may feel hopeless or lost and like you already experienced all the highs of lives, Horikoshi and MHA are here to tell you: There's always another peak yet to come.