Although super futuristic and heavily dramatized, I think the show "West World" depicts AGI pretty well and sheds light on some of the ethical points you touched on.
On another note, no one can deny that the presence of AI has been rapidly increasing across disciplines in present day. Why are you placing your bets on AGI touching down by the 2020s, though? What have you seen in your searches that makes the 2020s more plausible for mainstream AGI to arrive than, say, 2030s or 40s?
Great read, by the way.
RE: AI Is Completely Insane Stuff and It Is Oh So Close to Happening (Experts Are Freaking Out For A Reason)