>Do we really prefer to pretend dead people never existed in the first place?
I think that we consider facebook, a commercial entity based on data-mining every scrap of information it holds, an inappropriate place to memorialise our loved ones.
That's a separate question though. Fact of the matter is people do tend to put an enormous part of their lives on social media platforms. So it's on there right now, which is too late to consider if it was a good idea to trust an unreliable medium to steward your data to begin with.
What I'm concerned about is that when a friend or family member dies, you have to cope with the loss of the person, but on top of that Facebook forcibly arranges for you the loss of all corresponding data as well. They're effectively saying "Well, this guy's dead now, so we're taking away the documentation of all shared memories with that person. We're honoring the deceased by erasing their digital existence as best as we can."
> we're taking away the documentation of all shared memories with that person
They aren't taking anything away.
See my earlier comment about what memorialization actually entails. Nothing is erased, the content is preserved for family and friends. Of course the account status is changed, it would be inappropriate for a dead person's account to show up in lists of contacts to invite to events, and so on.
I think that we consider facebook, a commercial entity based on data-mining every scrap of information it holds, an inappropriate place to memorialise our loved ones.