Cryptographic identity verification and trusted clocks. As in, cryptography would be built-in and everyone would have a set of keys that they could use to verify ownership of digital content by using cryptographic signatures and timestamps.
Blockchains in a way are such clocks where the ordering of the blocks on the chain provide an implicit counter. But blockchains have too much overhead so by assuming some trust it would be possible to get rid of the proof of work mechanism and just use a signed timestamp from a trusted source.