I guess you did answer one question - you have no answers, only scapegoats.
I don't do it for "Zuckenberg". I don't really care about him at all. I assume if he didn't exist, someone else would have invented the same thing. After all, he basically ripped off the idea to start with. I do it because imo worse than dealing with obvious capitalist self interest that one can at least model and bound is dealing with people like you who treat themselves as some constituent of a crowd of pitchfork bearers rather than a serious civic participant. Irrational, virtue signaling outrage that I doubt you really even believe in or actually care about. Because what else are you doing about it? On your notion of "complicit" you might as well direct the same invective at your local gas station. I'm sure you will be able to find a relevant laundry list of perceived crimes.
Why don't you go through all those questions in order and actually attempt an answer? Or if the answers are so obvious and I'm such a troll, why has no one built a social network of comparable scale that avoids all these problems? Does the existence of Zuckerberg somehow preclude such a thing from ever existing? Is this another one of his malevolent powers?
Good thing our founders had the foresight to know the greatest check of all is on the people, so as to never let a mob establish guilt or innocence.
By all means, propose sensible social media regulation. If you can even conceive of such a thing. You sound like someone who has no idea what it is like to find yourself before some tribunal, some body with the power to judge human conduct as being "complicit" in some crime. The entire history of the West might be most optimistically summarized as endeavoring to hold such tribunals to the highest standards of objectivity and veracity. Have a nice day buddy.
Facebook knew what is going on.