To start off this review, I'd like to say that I've seen quite a few people complaining about this season. The main complaints seem to be about the animation and the lack of action.
I normally never write reviews, but, because of what I stated above, I'll try to express my opinion this time.
While I don't think starting with the animation is that relevant, I'd like to address the complaints here. The animation is absolutely gorgeous, it's the art style (yes, it's not the same thing) that has people complaining. I believe people just don't like changes, and, when something is indeed changing, they immediately react in a bad way without taking the time to think about it. To me, the animation is great.
Furthermore, the art change was made to stay true to the manga, so I think that's a good thing.
It does take a while (like 5 minutes) to adapt, but if you try to enjoy it, you'll see the animation and art style is pretty damn great. I personally like this art even more than the older season. It resembles the manga more, and seems more "modern". It is simpler, mostly because the animators weren't the same I believe. But it's still beautiful and satisfying to me.
Adapting to a different art style and seeing animation evolving shouldn't be such an important topic of complaints when it's done greatly! It's anime, OF COURSE the animation or art style is gonna evolve.
Secondly, the lack of action. I don't understand this statement either? Do people believe a good series is only matches with no character progression in between? This is what makes Haikyuu! so great : how we see the characters grow. Complaining about this is understandable if no big matches were played for some time, but this season follows the biggest match we've seen till now. Not to mention we still did get a quick match at this end, and we know the second cour is gonna be all about action.
Furthermore, if there weren't these moments where we see characters evolving, the show would become repetitive and boring, so I personally enjoyed it. Of course there's gonna be some training arcs, but if well made, they're interesting!
The focus on the first half is divided between Kageyama and Hinata, and it's incredibly interesting. I personally didn't see time passing when I watched each episode. I was engrossed in each of them!
To conclude, apart from some small pacing problems and some things being resolved too fast, it was still very good. I don't think this season is worse than the others. The characters are still lovable, the story leading to nationals is interesting, and the evolution of everyone's play (particularly Hinata) is great.
If you've loved the first 3 seasons of Haikuu and don't fixate on the art style just because it has changed, you're gonna love this season as well.