Of course, but those aren't trustless per my question. They're designed for single administrative environments like corporate data centers where a trusted entity controls the environment.

The other two possible environments being multi-administrative (permissioned DLT deployed among a consortium of banks or entities sharing administrative privileges) or no-administrative (public permissionless blockchains like Bitcoin/Ethereum). The hard problem is developing consensus algos for the latter that scale while maintaining security of the shared ledger.

What you mentioned does not cover byzantine faults... pow is the only known solution

There is a large amount of r&d being put into BFT-style proof of stake for Ethereum, it’s always been part of the roadmap. Much work still needs to be done beyond the test net, but so far no fundamental showstoppers have been found. There is also constant collaboration between the researchers and developers of major projects to move the entire field forward.

It’s still early days, unfortunately the hype got far ahead of the tech but progress is being made everyday. I think the same of VR/AR.

https://github.com/ethereum/wiki/wiki/Proof-of-Stake-FAQ

If only someone could think to google "BFT Raft extension" or "BFT paxos extension" and find published research. And if only papers from that search had citations. And if only those cited had links to foundational research on generalized BFT strategies. Oh if only we lived in such a world.

If only. If Only. IF ONLY. iF oNLY. If OnLy. iF oNlY.