(And btw Game of Thrones is full of 'special snowflake' characters, albeit in a low magic fantasy setting. I could outline the three main Stark pov characters alone to prove this point. Drama makes a good story, lack of it often makes a boring one)
GoT is based on books. The literary characters have more meat on their bones.
"People are so focused on their own intended playthrough experience they have allowed themselves to be blind to the other options available." Are they? That's just an opinion you have pulled out of thin air. I could just as easily claim that people are so focused on their own intended playthrough that they cannot accept that their choices are not being reflected by everyone else.
"You can certainly have an opinion on whether this whole idea was a good one or not, but use a bit of logical thinking when you're trying to grasp why they did it. " Why? Whether I think the idea is good or bad, I still think the origin companions are much of a muchness which means that if I dislike or am uninterested in one then I pretty much dislike and am uninterested in them all. Conversely I could like some or all of the companions be not be interested in playing as an origin character.