This is a POC, non working full concept.

I think I'll go with this:

Non reviewed content / pageshots will be displayed to all anon visitors with applied filter:

And once content is reviewed by "registered user", the filter is gone from anon public users as well

Peer reviews will help us build the metanet of trusted content.

Content review will be a process of stepped un-blurring, so no-one should see the possibly disturbing content, because they can mark content as disturbing without seeing full unblur (and spare reviewer's eyes before getting into detail).

Applying machine learning, like tensorflow, will help exponentially. When more content is reviewed, AI will be smarter and so we don't need to increase human reviewers on increasing content.

Videos can be done same too.