tl;dr, "my friend died but Facebook hid the post from me so I had no idea."
Facebook employees, how does the company react internally when it fails to meet its mission? Do people feel bad? Does it inspire teams to do better? Does anyone even hear about incidents like these? Does anyone care?
This isnt a new problem, fwiw. People have been reporting this kind of algorithmic information theft for a long time. Is anyone actively working on this?
But that's okay. You're still supposed to see posts from friends you've interacted a lot with near the top of the feed. That's the only signal FB has on whether you're close to someone or not, apart from you specifically saying so.
The author also says:
"Now, I'm a meticulous FB feed peruser. I always set it to Most Recent and browse until I see the stuff I saw last time. I keep up."
Could that be what caused them to miss the post in the first place? If you're always setting your feed to Most Recent you make it harder for Facebook to gather signal on what's most important to you. Plus, although they say they "always browse until the stuff they saw the last time," we all know the chances that they do that 100% of the time are pretty low. Maybe they missed the post that way?
I don't know why/how they missed it. It is definitely sad and I wish it had turned out differently.