Nightcrawler has the potential to ask as an ideological Rorschach test. One of the key ideological differences that shapes one's worldview is whether you see the world largely as a place of individual actor, with society comprising the sum of their parts, or whether you see society as a system that ultimately molds those who live within it. The former view would see Lou Bloom (Jake Gyllenhaal) as a uniquely, morally corrupt individual, alongside a number of other less than noble actors, that exploit and create the "if it bleeds, it leads" local news system, in this case represented by Nina (Rene Russo). The latter view might see Nina and Lou as human beings who, if not exactly average, are at least not monstrous, rather, the social context pushes them toward some rather distasteful choices.
Either view has a certain legitimacy, and I can see the uncomplicated appeal in simply drawing a clear line and blaming these characters for their actions, punishing them, and hoping that solves the problem. Unfortunately, and why I tend to subscribe to more structural approaches, is this approach doesn't solve the problem. An individualist approach would blame specific individuals for holding racist or prejudiced views, a structural one would see how the media shapes views by being selective in the type of stories they report, in this case focusing in on the suffering of middle and upper class, mostly white, especially as caused by the poor and non-white. But the news programs aren't crafting this message because they have an ideological attachment to racism, they do so because those are the stories that will capture attention. It is irresponsible, but it is what drives their ad rates, thus their ability to survive. And the viewers interests are probably shaped in some way by this so it becomes a destructive circle.
For Lou, you see an incredibly crafty, entrepreneurial individual who should be able to succeed in any number of things. However, because of his lack of formal schooling and an awkward social manner, he finds himself largely blocked from more legitimate channels (lack of opportunity leads to criminal activity, leads to criminal record, leads to lack of opportunity). And so in an economically desperate situation, he opts for the shady business of filming crime scenes for local news, and following on incentives presented to him, seeks increasingly unethical approaches to maximize his value. Rick (Rez Ahmed) enters in as an employee that is even more desperate, and thus even more readily taken advantage of. Instead of these two desperate souls, and the others out there, working together to change the system however, they largely take each other down, classic divide and conquer. Through the interactions of Lou and Nina, we are presented with implications of this structural sickness on romance, with Lou representing patriarchy in the way he exerts a coercive power over Nina. Even though she is in a seemingly superior position, he is able to exploit a few specific weaknesses.
Creating this thematic basis is impressive, but it wouldn't work nearly as well as a film if it wasn't so expertly constructed. Highly stylish and jet black in tone, there is a compelling sleaziness to it all. The way the end-game plays out had me largely holding my breath for the last half hour or more. In this the film is playing a bit of a meta game. Capturing our interest in this way in large part proves the point of Lou and Nina, in a sense justifying his action. In our defense, we know this is a fictional movie, he is operating in the reality of his world (though often distanced from it through his own viewscreen). This way of accusing the viewer of hypocrisy isn't novel, namely seen in Funny Games, and if it were the main thrust of the film I'd probably have found it as unappealing as that film, but added as another layer upon the more socioeconomic relevant parts, I'm willing to revel in my own hypocrisy because hey, it isn't my fault, I'm a victim of the system same as anyone else.