Having experienced this myself first-hand:

It's not hard, but you need to know that telling FB that your friend is dead is even an option, then go search for that. For most of us that probably seems pretty simple, but we're definitely the outliers in regards to technical sophistication and knowing how a site 'should' work.

In addition, there's the 'etiquette' of trying to figure out if you, as a friend, should do that, or whether you should leave it to their family, and then wondering if their family even knows about their FB profile, etc.

As the article pointed out, 'there are likely far more accounts that haven't been memorialized' - which suggests that people don't do it.

That's fair. If I didn't do it for my mom, I doubt it'd have been done. I don't even think I'd consider doing it for a friend, that's something I'd leave in the hands of whoever has the death certificate.

Facebook surely indexes a lot of the internet, "AI techniques" like entity resolution on obituaries would probably go a long way to finding unreported deaths.

I seem to recall there was an important caveat to memorializing an account, but unfortunately I don't remember what it was. Anybody know?

Probably that once you do it, if the account holder had previously set it up so, you might end up triggering deletion of their account. A lesser caveat is that without a previously specified caretaker, the account will become totally locked down, whereas a caretaker can still change the photos or pin messages etc.

Oh yeah I think it was one/both of these, thanks!!