The top comment mentions people hiding posts from pages they don't follow - alternatively, that's called showing brand new content you haven't seen before.
Opposing material suggests a binary, sure that makes some sense in a US centric political spectrum, but what's the opposing viewpoint to my friends photo from hiking last weekend?
Geographically nearby could mean my neighbor 5 doors down who I don't know anything about and am not friends with. Do you think, if she were a privacy-concerned individual like many people on HN are, she'd be happy to know I saw her post about her new flowers?
It's less narrative control and more human condition - if anything I'm glad they tried this experiment. Chronological feeds are how you end up with news teams spamming posts every three minutes, and you having to hit the hide button every time.