I am reviewing this show not to make you get into Haikyu!!. This is more so to give you my main opinion on this season. This is not a review, but more so a discussion. Obviously, there will be spoilers if you are not caught up to Haikyu or at least S4. Now that that’s out of the way, let’s talk about the show.
Season 4 starts off after Karasuno’s victory. After Kageyama is invited to the All-Japan Youth Training Camp., it seems like he is showing off to Hinata. But it is quickly revealed that he is just provoking home to catch up to Kageyama. With the Youth Camp, we are introduced to all the new rivals and antagonists. Over on Hinata’s side, Tsukishima is invited to go to a special rookie select training camp for first-years in Miyagi Prefecture. As both of his rivals are invited to train with some of the best players, Hinata feels left behind. As the mad-lad he is, he breaks into the training camp Tsukishima went to. After he’s caught, Yashijo makes Hinata the ball-boy(Yaoi artists be sweating right now). With all the characters set up, let’s talk about the antagonists.
The best part of this season is how it builds up to the 2nd part. The new characters perfectly maintain the momentum between S3 and the 2nd part of S4.
All of the characters especially Atsumu and Hoshifumi are amazing rival characters for Kageyama and Hinata. Hoshifumi’s incredible similarity to Hinata is what I was waiting for. Throughout I thought that Hinata is really underwhelming because he’s only rival is Kageyama. That’s why every time he’s growth is influenced by characters like Kenma or Bokuto, it feels a bit too immature. I don’t hate it but I thought there were better ways to handle this. That’s why seeing Hinata be intimidated by Hoshifumi and the clear difference between them will lead to an amazing showdown in the second part.
Atsumu is a 2nd Oikawa. I think everyone gets that. His cockiness and extreme immaturity but undeniable talent make him a perfect role model and rival character that Oikawa was. His influence on Kageyama right in the first few episodes is mind-blowing. I advise you to watch Aleczandxr's video on Kageyama because he will be able to explain this better than me.

▶ Atsumu’s provoking pushed Kageyama to be a lot more strict on his team but not exactly like how he was in middle school. This perfectly explains what Oikawa meant to say in Season 2. This makes me keep on watching Kageyama’s development and like him more I have talked to some Haikyuu fans who don’t like season 4. Most of their reasonings are that this is not that this season does not live up to the same hype as season 3. Well yeah, but the main point of this season is to build up all the characters and this is done marvelously. It perfectly hypes me up to watch the new season and lays down all the plot points. Season 4 is underrated because this is more character-driven and does not have the same level of hype as the other seasons. The whole point of this “review” was to explain to you the point of season 4 and change people’s opinion on it. This review may have been a bit messy but I think I was able to say what I wanted to say. If you want me to review a show, message me or DM me on Twitter. (Links in my bio.)