While we're still in the dark about the details of Deku's present situation thanks to it being an end-of-chapter reveal, it's clear he dropped out of U.A. High School and intends to leave it behind for good. For the next phase of the story, which signs suggest maybe the last, the "academia" aspect of My Hero Academia seems to have concluded.
Some fans are theorizing that Deku left U.A. cause he’s the traitor, that he feels guilty betraying his friends, and he’s off to do villain work. All these statements are false. Deku is not the U.A. traitor. He did not leave because he was framed to betray his classmates and teachers.
Why Deku Had to Leave U.A. In Chapter #304 , Deku was told that he was the last wielder of One for All and is the superhero society's last hope to defeat All for One. He recognized that he didn't have a choice anymore: he couldn't walk away from his destiny so he had to walk away from U.A. and his friends.
The speculation says that Deku will leave Japan and go USA to train under other Heroes and gain more experience. Though this is not confirmed, yet, there is chance. The way Midoriya has left UA Academy, it symbolizes that he is going somewhere far away. and far away may also mean leaving the country altogether.
In the anime, it's the start of second term of the school year in Japan, so it's currently September. He started attending UA in April. So, five months or so.
Deku left U.A. to guarantee the lives of his mom, friends, and teachers. He is neither a villain nor an anti-hero in the series after dropping out of school. If he does become one, not only does this character shift too late at this point in the manga, but it's not also within Deku's “Shōnen character template”.
Mina asks Deku to rejoin the U.A. High and attend the classes. Deku makes it clear to Mina that he always likes to join them, but if he comes back, all his classmates will be in danger. However, Deku later rejoins the U.A High.
Izuku decides to leave U.A. High. He leaves notes to all his classmates in his absence, revealing the secret of One For All, as well as his connection to All Might. He also reveals that All For One and Tomura will be pursuing him.
Deku is not the U.A. traitor. He did not leave because he was framed to betray his classmates and teachers. The current arc of the manga hasn’t confirmed the identity (identities) of the traitor (s) yet.
Deku’s departure is essential because not only does he need to stop wanted criminals like All for One and Tomura from decaying another city to dust. Rather, he must also protect citizens whom he can reach with his own two hands. To do so, he must leave U.A.
Izuku Midoriya is in the middle ground and this is an intentional turning point that is coming from the author. Deku must hold onto whatever moral fibers he has left on his body and push past these challenges if he wants to save the world and save Tomura Shigaraki.
And for another thing, he has limited informational resources (e.g., inability to access the Hero Network, losing communication with his close friends and allies in U.A., etc.). If he’s unable to gather intel, Deku doesn’t have a choice but to move at a snail’s pace to hunt his enemies!
1 hero of the hero society since the start of the series. Henceforth, “Villain Deku” is not someone MHA fans can see in the main series. However, I’m not ruling this possibility completely. We won’t know what’s going on in Horikoshi’ s mind.
Deku has not turned into a villain in the series. Many might think that now he’s off U.A.’s leash, he can pursue villain works immediately. But that is not the case.
If he remained at school, he would be drawing danger to their teachers and classmates. School is a symbol of childhood and with Deku being forced to grow up early and fast, it makes sense that he would be the one to drop out of school first.
In Chapter #304, Deku was told that he was the last wielder of One for All and is the superhero society's last hope to defeat All for One. He recognized that he didn't have a choice anymore: he couldn't walk away from his destiny so he had to walk away from U.A. and his friends.
In My Hero Academia, it's saving anyone who needs help -- even if they're a villain.
Deku, being one of the few to see that behind the villainous mask is a terrified young boy -- not that different from Deku himself years ago -- wants to use OFA to save him.
Deku needed to go to U.A. so he could train his new Quirk and the Academy provided him the right environment and support system to do so. Despite how many times the school has been attacked by villains, it has nevertheless been a safe haven for students. And with the teachers being Pro Heroes, the students could always count on them to be there when things looked bleak. Deku knows he's been very blessed for getting the chance to go to U.A. because it's gifted him so many opportunities, including being mentored by All Might and finally talking to Bakugo on (somewhat) equal terms. But with Shigaraki and the villains continuing to grow in strength and numbers, he knew he couldn't stay in the comfort and safety of U.A. any longer.