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  1. Steemit is still far from Google in terms of data stored, but even the strongest links in the witnesses chain are far from Google's data center.
  2. Google has only 1 data center, which may probably be backed up once or even twice, but Steemit has to have many more backups.
  3. Google can delete when necessary, Steemit still does not.

A future hard fork could discard all flagged/hidden content in the future, yes?

I'm not saying this would even be a good thing, necessarily, but the potential is there to shed parts of the database based on witness consensus?

Good points, thanks for the information.

Automatic deletion of flagged content is a bad idea, due to reasons @seraph exists for, and for more reasons Steemit exists for.
Still, there should be additional judgement (human, or even AI) taken prior to a deletion.
But deletion must be done, because the current Steemit model is self-defeating.
Look at sherlockholmes' work.
How this place demands deletions

Yeah, that's what I meant. Not an automatic deletion so much as community-agreed guidelines for filtering some stuff for deletion.

I really like the concept though the content can only be hidden, deleting blocks will actually de-value steem if im right.