Isn't the premise of the story that you're a character thrown into this situation? Aside from the characters around you telling that "x" is what you should do, has the character any background, pre-game reason that makes clear that she/he wants to do x? I'm genuinely asking, I only experience ME through the comments of other posters -and my pre-conceived notions of bioware games-.
Not exactly. ME2's and 3's premises start with the player character, Commander Shepard, being committed to stopping the Reapers and saving the galaxy.
This is why role-playing options should be designed around maximizing the story's premise, not fighting against. Let's take Inquisition, as an example. Back cover:
"Recruit Legendary Warriors to fight by your side as you hunt down agents of chaos and lead the Inquisition. Only you and your team can bring the world back from the brink of destruction".
Also, yeah, of course you can't implement every choice, you don't have the resources. But from my understanding, the poster I was replying to was referring to a choice that was in fact implemented, so obviously there were resources available for it.
Right, but the suggestion from the poster was that those resources were wasted. They also weren't part of the original ME3 endings, but were added due to fan complaints of wanting to be able to "refuse" the main antagonist's choices being offered to the player, which later added fuel to the fire because players wanted to refuse and win against the antagonist. Bioware implemented the former portion, not the latter.