That’s a nice flowchart. Also, blockchains are only applicable when you don’t know anyone you trust to run your infrastructure. I don’t think this is often true

That’s a nice flowchart. Also, blockchains are only applicable when you don’t know anyone you trust to run your infrastructure. I don’t think this is often true in practice. Blockchains are also only needed in situations where you need a single, global source of truth. Ie, where eventual consistency / gossip networks wouldn’t be good enough. So blockchains are needed to avoid the double spend problem, but plenty of real world software can get on just fine without a single central ledger. (Eg scuttlebutt, CRDTs, etc).