Seconded. After about 30 minutes in I had to start taking notes about things that bothered me. Some highlights:
SPOILERS BELOW
The acting is bad, yes, but the script is not much better. There are so many places where they seriously oversell something. The classic maxim, "show, don't tell," is very appropriate here. Often times they approach something so straightforward, so on-the-nose that it is hard to take it seriously.
For example, there is a scene that I assume was shot solely to explain how apathetic the interrogators are towards the prisoners because it has almost no further plot significance. They have the guard say, basically, "I don't care about you. If I come in tomorrow and you're not here I don't care. I'll just interrogate whomever is here. It's my job." And while I think that's a poor script, a really good actor could probably sell it to be intimidating, but that didn't happen. It was just boring. Really boring.
Another example is the pair of agents that interrogate hash. The younger one is super aggressive, to the point of being comical. The older is super laid-back, again to the point of being comical. I don't get the feeling that either was suppose to be comical, but they are so one-dimensional and obvious that it is.
The call out to the CSI-style "enhance" was another example. Sure, they had to include a realistic version of that, but the whole scene reads like that was the only point of that scene. Like on the storyboard they just had, "This is where we make the joke about zoom-enhance." Or like they had some checklist of things to make sure they referenced.
You are exactly right also about the proselytizing about superficial hacker culture. I don't get the impression that the main character is an elite hacker with strong convictions about the way the world should be who stumbles onto something. I get the impression he's just a script-kiddie with the soundbite morals of a teenage hacker wannabe. Anyone who has been around for more than 13 years has a more nuanced understanding of the world. Being idealistic doesn't mean you have to have a view of the world that is black and white to the point of absurdity. I guess that would not have been so bad if his views evolved over time, but like you said: no character development. To make it even worse, after spending so much of the beginning of the movie explaining how life-defining his beliefs are he just abandons these core tenants of his world-view at the end like they're nothing.
Also missing is a sense of proportion or even consistency of urgency. Sometimes other characters will freak out over something that happened. But then the next scene you have "yeah, that stuff happens when you hack the government. Shouldn't have done that." Or the government agent who implies, casually, that after a minor mistake she was tortured to the point of not sleeping for days. Like it's no big deal, just part of the job. We torture employees and terrorists alike!
The torture scenes themselves were exemplary of the boring nature of the movie. I loved the "worlds can explain how horrible something like 20 days or torture is" so now let's just show you the words "20 days later." They literally had that voice-over on top of those words. I'm sorry, saying "It was indescribable," doesn't do anything to sell me on the reality of it.
And that's not even addressing the huge plot holes, or trying to understand what the point of the movie actually was (because it definitely wasn't a compelling story). Don't waste your time with this one.