>The root problem with conventional currency is all the trust that's required to make it work. The central bank must be trusted not to debase the currency, but the history of fiat currencies is full of breaches of that trust. Banks must be trusted to hold our money and transfer it electronically, but they lend it out in waves of credit bubbles with barely a fraction in reserve. We have to trust them with our privacy, trust them not to let identity thieves drain our accounts. Their massive overhead costs make micropayments impossible.
http://satoshi.nakamotoinstitute.org/posts/p2pfoundation/1/#...
Even the whitepaper has a bit about the weaknesses in financial institutions in the intro: https://bitcoin.org/bitcoin.pdf
The ideological/theoretical purity of cryptocurrencies is completely negated by using exchanges and by the perverse incentives of proof of work leading to enormous returns to scale for those who have developed custom ASICs.
Decentralization requires more effort than centralization, but something that requires effort doesn't generally grow very fast... And so we've centralized cryptocurrencies in a haphazard way, making them a lot easier for people to use--thus enabling cryptocurrencies to grow very fast--but also negating all the theoretical benefits.
Something useful will eventually come out of the current mess (and there are various initiatives that help address many of these flaws), but probably not before the Zeitgeist becomes disillusioned with cryptocurrencies.
Everyone criticizing the current state of crypto as being worse than banks is missing the forest for the trees. These systems are early tech. Ethereum is barely 2 years old. It was easy to criticize dial-up internet, too. I'm sure Barnes & Nobles scoffed at Amazon at one point. Easy to do this, and assume this "dot-com" thing is just a bubble that's going away at some point.
Decentralization is ONE feature of crypto currency. One of several. It's not decentralization alone, but the combination of features that brings value to crypto, including programmable economic incentives (a powerful concept we're just learning the implications of).
To answer some of your other points: even exchanges are being built on the blockchain now. We have 0x, EtherDelta, etc, which allow you to trade tokens without revealing your identity. So, that problem is starting to resolve itself.
We have Proof-of-Stake coins like Qtum, which avoid the Proof-of-Work issues (Ethereum will be moving to PoS soon).
Still not sold on the idea that proof-of-work is inherently bad though. I consider that system very secure, as Bitcoin has proven. The blockchain itself has proven quite resilient to hackers, DDoS attacks, government intervention, etc.
Then again, given that Satoshi's true identity is unknown, a lot of this is necessarily speculation by interpreting a small set of clues.
Satoshi is a team employed by something very rich, probably a government.
what
Bitcoin is just the clever but natural progression from previous cryptographic cash systems like b-money. The cypherpunks mailing list had long been interested in making more decentralized cryptographic cash systems along those lines. The fact that one of them finally combined the right cryptographic primitives in the right way to make such a system is hardly a sign of any insider knowledge or outside influence.
The creation of Bitcoin was by someone who had been following the cypherpunks' progress in the area for a long time, and finally noticed a clever way to combine standard tools to get the job done. There's certainly nothing superhuman about it. It hardly looks like a problem that was solved by a government throwing money and a team of pros from out of nowhere at it.
In the actual white paper, Satoshi does not mention any of this, although like you, I do remember these motivations being used very early on. I don't know their origin, but Satoshi simply talks about non reversible transactions, in the context of payments over the Internet.