Fantastic, thorough post! It's worth mentioning that in our algo-driven age nearly everyone seems to forget that the algorithms have one goal in mind: maximize profits.
In the case of FB they purposefully promote irrational, inflammatory content so that it divides people with different opinions and consolidates all of the like-minded people into the same group.
With all of the like-minded people all gathered into neatly prepared, concentrated, online groups they can then target ads at these groups more effectively. They are able to say we have 5 Million people who support Hillary, enjoy chocolate ice cream, like alternative music, and read fiction, and then sell this group's personal information to advertisers who have an interest in these demographics.
In essence, they are dividing and conquering our social circles and then re-organizing them into what is the most convenient possible way for advertisers. They are advertisement curators.
At the end of it all, the algorithms in social media are a farce, as are the ones used in financial modeling. Much like any other model, it will work until it doesn't.
RE: "Why Talking To Me Pisses You Off"