I wouldn’t consider only the content/feed selection algorithm - I would take a holistic look at how people interact with Facebook (like button only initially, then expanded to a few more choices; real identity, not many comments shown at a time), then also compare it to other sites and their outcomes like Reddit (up and down votes, anonymous if you wish, lots of comments shown at a time).

Regarding users bearing responsibility for what they consume - I have seen others report running into this and I have as well - no amount of feed grooming keeps the controversial content off my feed for a meaningful amount of time. I actively unfollow / snooze content I don’t want to see, but Facebook has countered this by adding “suggested for you” items to my feed. It’s impossible to only see my friends’ updates. I must be exposed to the negative stuff as a cost of using Facebook.