I'm writing this review mostly to help others manage their expectations before watching this movie.

It starts slow and confusing. You get to chuckle a couple of times before being introduced to one of the most unnecessarily inhumane scenes. The antagonist is a monster and the movie doesn't stop driving that home to the viewers. Not once, twice or even thrice seems to be enough.
With all the chaos going on all the time, this movie still manages to feel draggy. The somewhat amusing scenes start to feel flat. The finale itself seems to drag on and on. The ending is unsatisfying.

I'll mention a few positives at the end.

Before continuing, I'll just point out that I was most disappointed because I was expecting an action-comedy movie I could watch with my family. Nope. To sum it up: it's too brutal with little to no context or character development to the point it gets boring and forgetful.

Most relevant characters are barely acknowledged. The opening scene that's supposed to introduce us to team good guys is a mess. It's 99% skippable and unnecessary to the main plot. You only get a gist of who the main character is and his surroundings but get nothing substantial that makes you really root for this guy.
The antagonist is at such a crazy level of monstrosity that at some point you don't even want him on screen anymore. His scenes just show you over and over again how disgusting of a human being he is. All that screen time could have been used to flesh out other characters instead.
Somehow this movie makes you feel like a passive bystander instead of someone truly invested in the story. Even though you want justice, you don't really get attached to anything. You simply watch things unfold almost indifferently.

So, some positives before concluding.
I found the level of chaos in the conversations, confrontations and fight scenes gave it a less "staged" or "clean" feel than what we usually find in other movies. Sorta realistic in a way. But somehow still less entertaining. Ups, this is supposed to be the positives section...
If I have to say something else good about it, I guess the actors did a good job.

To boil it down to one problem: ultimately, you don't really care about the good guys, you just want the bad guy gone and feel sympathy towards the victims.

Watching the trailer, reading the synopsis and some comments, I imagined something completely different: something fun, clever, with great teamwork, sacrifice, high stakes, etc.
How could it be so lacklustre instead? The victory at the end doesn't really feel earned. Protagonist and antagonist have no chemistry. They could be facing other people and it would be the same. There are no character arcs. Every character remains the same from beginning to end. There are too many small and not-so-small details that just quickly fade away into the background. Any intended message gets buried underneath all the overbearing violence, yelling and overly fast switch between scenes.

Alright, I've ranted enough. Hope this is useful to someone.