I don't get what's supposed to be funny here. So a main character is a douchebag who walks around insulting everyone he sees for no good reason. Aahahaha so hilarious. Real clever way to spend your VA budget. And let me guess, there are parts in game where this same douchebag is also giving whiny speeches about how fucked up the world is or some shit like that, and the game expects you to think it's smart. I'm only guessing it based on the way characters would sometimes speak in GTA V.
The main character is one of the most well-developed and incredibly designed and performed protagonists in the entirety of video games; the antagonistic behaviors and responses are there as a choice to enable the player to have him engage with the world in a different way. For my part I hardly ever use the antagonistic responses unless I'm being threatened or am committing strong-arm robbery. As for speeches about the world being fucked up, I'm not sure exactly in which way you meant that but if you are making an association with Grand Theft Auto then no, absolutely not. The games are similar in design at a fundamental level and the narrative and missions are handled sequentially in much the same way, but they are profoundly different in intent and even the themes of outlawry and criminal organizations are handled very differently. Arthur isn't a nihilist or absurdist and isn't used as a mouthpiece to humorously denigrate all of existence; he makes casual remarks about wondering if life is just a waste of time and such but the majority of his commentary and dialogue is one of deep feeling and strong emotions. Then there is his journal, in which he draws pictures of every single animal in the game (and the more you study, track and hunt them, the more detailed those drawings become) and write about almost every event that occurs including dozens of minor and randomly generated encounters. In reading it you gain much more insight into what motivates him, what his fears and anxieties are, for whom he holds affection and who he deeply mistrusts, past regrets and lamentations of losses incurring deep suffering, etc
Whether or not he is a douchebag is subjective of course but largely comes down to how the player decides to interact with the various environs and the NPCs inhabiting them. If you want to, you can mercilessly insult people, you can actually stalk them and watch their nervous apprehension increase, you can rob strangers and passing travelers, stick-up coaches and rob entire trains. If you choose, you can kick dogs and cats and jeer at them, punch horses in the mouth, light pretty much anything and anyone on fire or explode them with dynamite, hogtie strangers and leave them on train tracks or load them on the back of your horse and then ride out into the sea causing them to drown, or slit their throat, or choke them to death, &c. But you can also assist people in need of help, remark on events positively and greet every single person in the game with idle pleasantries, rescue people from certain death, give rides to stranded individuals, donate to the poor and homeless, and so on. How much Arthur is a douchebag of ceaseless misery and hatred, or a wonder of a nuanced, deeply complicated and traumatized man riddled with insecurities and doubts which lead later on in the story to devastating remorse, is entirely up to how the player determines him. There are hundreds of minor and dozens of major choices to make that change how he behaves and how he is perceived and treated by other people. The more you antagonize people and commit crimes, the harsher his insults and dispassionate his ironic fatalist sense of humor will become; contrariwise the same thing unfolds in the opposite direction, so that the kinder you are the more sincere and heartfelt his greetings and responses to strangers and friends alike will become. Even though the choices are basically binary there is a remarkable sense of development with a broad range of disposition and temperament as your reputation and honor level go towards either extreme.
Grand Theft Auto is generally a self-aware fourth wall breaking nihilistic affair of dark humor and edgy immaturity with only occasional instances of insight and meaning. Red Dead 2 is on an entirely other level, one I would even go so far as to say approaches spiritual heights that have never before been reached in the medium. The circumstances of despair, the questions raised about fate and choice, the tragedy of heart-breaking losses of innocence being rent impure, questions of mortality, of creation and theology, there is just so, so much more to this game than it seems people can even begin to fathom. It is regrettable that Rockstar is so inseparably bound up with Grand Theft Auto that a masterpiece of this sort cannot but be blemished by association. And in the wake of Dan Houser quitting, I suspect we will never see the like again. The game is so many things on so many different levels, but ultimately it is to me a meditation on life and loss, a period piece exploring the end of the frontier spirit being trampled underfoot as industrial urbanity crawls westward and a character study of the last remaining efforts at remaining utterly free from civilizational restraints, except they are led by a deeply flawed yet endearing and visionary leader who in my opinion succumbs to inner demons. It is a shame that people miss out on this game due to preconceived notions or hive mind insecurities, or if they do try it they tend to quit before finishing even the first (essentially tutorial) chapter because they assume the game is totally on rails and more of a movie than a game. This is just absolutely not the case, with an open game world that is astonishingly vast and filled with thousands of secrets and random encounters that despite hundreds of hours and numerous play throughs I still am encountering new instances of with every play session. I only half-jokingly suggest to people that the developers keep patching in new encounters somehow stealthily, because it is just inconceivable to me that a game can possess such vast content, hundreds of thousands of lines of dialogue that is dynamic and so highly variable. I'd read that it contains over 500,000 lines of dialogue and over 300,000 animations, which is simply a staggering achievement.