While the second opening was disingenuous to the heart of Izuku's solo arc, the actual content of the anime itself has remained quite faithful. Even going so far as to add or change some details to better represent the characters and their feelings. It's almost as if these changes were an amendment to the manga, just in case the manga didn't answer certain questions well enough.
Like the true reason Izuku decided to leave U.A. The manga presents Izuku's loved ones as a group, with Katsuki there as the last person your eyes should look at. But will readers make that connection? With the removal of just one word in the anime, the group part of the sentence, it shows viewers a more solid, concrete reason: It was explicitly because of Katsuki nearly dying.
Another example is how the various translations of Katsuki's line ("waatteru") created fandom friction, and they would flitter between "I know" and "We know," depending on who was translating it.
I always thought it had a very personal "I know" vibe to it because as Katsuki stated, and this is something reminded to us only 3 chapters earlier: He is the person who "knows" Izuku best. The anime removes ambiguity of the I know/We know debate by having Izuku apologise only once he'd made it into Katsuki's arms, making their exchange of words appear even more intimate and direct to one another. Katsuki knows.
Then after he stumbles his way into Katsuki's arms, there is that bonus clip of him being awake to hear Katsuki's gentle forgiveness of him. To express that the last of his resolve has crumbled because of Katsuki’s apology and being held in those arms he feels safe. He feels loved. So Izuku gives himself fully to Katsuki's care, murmuring out his beloved’s name with a "Ka…” right before finally succumbing to sleep. I think this extra moment makes the feel of their apology seem even more romantic… because it's supposed to.
And now Ochaco's handhold! It being featured in the opening gave some of us grief every week simply because this arc was never about IzuOcha, it was about Katsuki and Izuku.
Katsuki realising his need for Izuku to be by his side and losing SLEEP over not knowing if he's okay. Katsuki's proud statement of knowing Izuku best and that he couldn't be left alone because of his disregard for himself. Katsuki instigating the search and rescue of Izuku. Katsuki humbling himself before Endeavor and Nezu, setting aside his pride in exchange for the safety of his most important person and best friend, PLEADING Endeavor for his help because he's SO AFRAID of Izuku being out of his sight and losing him forever.
Katsuki saving Izuku's life again. Katsuki humbling himself a second time, apologising to Izuku and telling him to put some trust into him and their hero friends; that they can be relied on to help him. Katsuki telling him his ideals of saving people weren't wrong, and they can only win by saving everyone: Izuku, the people at U.A and the people in the city.
The beautiful poetry in Izuku’s reason for leaving, to protect his most precious person, being overtaken by his reason to stay: Izuku’s unconditional, everlasting love for that person and his overwhelming need to be by their side. And here Katsuki was, finally telling him it was okay to; he wants him there.
Even Daiki-kun said the last of Izuku's resolve left him because of Kacchan’s heartfelt apology… Yes. The opening’s handhold was really out of place.
And after Izuku is brought back to U.A, we get to the real IzuOcha handhold... But rather than grabbing his hand like she does in the manga, they have her grab the more impersonal wrist area instead. It's so hard to believe we are in a timeline where Bones are making an opening Ocha-centric, when it shouldn't be, and yet NERFING her handhold in the ACTUAL anime content…??????
All of this has got me thinking that maybe Hori himself has been directing Bones to make these changes - to make BkDk's growing love for each other a more prominent fixture in the story that’s almost impossible to miss, while dampening the IzuOcha teasing into little more than kindness between two good friends. And in doing so, the anime has now become spiritually connected to the manga because this is the exact same direction the manga has been going in lately.
Why else were all of these changes and enhancements made in the anime? Maybe it’s because Horikoshi is preparing people for the bkdk romance that's about to go into full bloom.
