That the game's NPC usually don't treat you as such and ending slides don't reflect it doesn't change that in gameplay terms you very much are the usual chosen one video game protagonist who develops from a rookie to a killing machine in a very short span of time. You're not just some soldier among dozen of others when major events in the game play out very differently without you participating in them, it's C&C course but it also showcases the heavy impact your PC's actions have.
I mean let's examine the combat focused path, you start out as some random semi-competent bouncer and rise up to become an arena champion, activate and wear the magnificent piece of ancient technology that is Power Armor, regularly take on groups of dozen people single-handedly (and many of them compose of trained soldiers), amass a 200+ bodycount and quite possibly end up punching out Cthulhu, all in a span of a few months or so? Regardless of whether the game goes the Bioware route and gives you constant blowjobs for achieving such epic feats or like AoD insists you're still largely insignificant in the larger scheme of things it's still essentially your usual zero-to-hero progress in terms of gameplay typical of CRPGs.
Now don't get me wrong, I love the game and consider it to be the best RPG to come out in the last 10 years but I'd say those specific design goals you mentioned are achieved only in the Teron part of the game where taking on even 3-4 people can be a nail-biting affair (as it should be in such a setting). They start to apply less so as you advance through the game and get to a point where for example one of the Centurions in Caer-Tor casually asks you to prove your worth by taking on 5 raiders on your own (whom you proceed to crush like insects with a combat oriented char).