Horses for courses
In most cases, a centralised infrastructure is what you need because that's the one that can best scale, operate more efficiently etc. By "centralised" I don't necessarily mean there is one channel / processor, but that there are multiple levels of grouping, exactly like e tree from leaves to branches to bigger branches to trunk (and ideally having multiple trunks). Of course it requires trust in that 'trunk', but you also get legal oversight and ultimate responsibility.
The blockchain is completely peer-to-peer with every peer communicating with every other peer. This is terrible for scaling (which is why Bitcoin can only process a handful of transactions per second), and it's *only* advantage is that it is completely "trustless" in the sense that you do not have to trust a central controlling authority. But as Perlman points out, if you're transacting with an individual, you still have to trust that they will deliver what you are paying them for. Of course if I use bitcoin to order something online from a reputable company and it doesn't get delivered I can still sue the company just as if I paid by credit card, as long as there is a transaction record such as an email order confirmation - there is a public record of the actual transaction on the ledger. It's for illegal stuff like buying drugs or ordering a hitman that someone doesn't have any recourse if they're defrauded.
I also see here a very skewed view of Bitcoin - it's used to 'hide' from government, therefore is used mainly for criminal purposes. That reflects a complete misunderstanding of why Bitcoin is mostly used - as a store of value, not as a transactional currency. As many silk road drug dealers found out, Bitcoin is not, in fact, anonymous. It is at best pseudonymous, but real wallet owners can be identified through transfers within the Bitcoin network, and between Bitcoin network and fiat accounts. The main 'selling point' of Bitcoin is that no single entity can "cheat" by creating new Bitcoins without proof-of-work, the amount of Bitcoins mined is limited, and the ratio of newly-mined coins to existing coins is tiny (thus giving it value-holding characteristics much more similar to those of gold). On the other hand, value stored in fiat currency as cash or savings are eroded by inflation and cost-of-living increases, and "safe" investments give returns that are worse than inflation.