[xtracto]

I think technologically a blockchain like DB could be implemented I Cassandra: every person has a node which replicates n% of the ledger. We implement a "block-chain" verification system by hashing the content of each previous transaction and there you have a ledger.

The main issue is concensus in a distributed system were we dobt trust each other (i.e. no central source of truth/authority) If 2 transactions collide/conflict with each other, who do you trust? Who has the last word? How do you prevent double spending? (Given the eventual co consistency of the DB and an adversarial environment).

The truth is that these questions and more are answered to a certain degree by different Blockchain protocols. Delegated Byzantine Fault Tolerance is one, PoS is other, PoW yet another and we even have crazy ones like Chia (proof of space time).

It's like the token ring vs star topilogies ir ipx/spx vs tcp/IP or http vs gopher vs ftp vs nntp vs smtp.

Did you know that around the 90s there were a lot of us purists that made a lot of noise because people were sharing files in a very inefficient way through SMTP? you've got to base64 or uuencode it... its wasteful. FTP instead was made for file transfer.

The same thing will happen with blockchain technology. Inefficiencies will be ironed out.