Hmm, calling bitcoin slow is a little strange. Are you talking about confirmations, where other networks take 100s of days? But since it's "not a technical post", I wonder whether technical knowledge is invited to his discussion.

Whether confirmations happen instantly (violating physical speed of light constraints imposed by reality) or take minutes or even months (ahem, Visa etc), does not seem to play any important role into whether something is fit for a consumer product. I'll give an example: even in the case of Visa's network, consumers are somewhat isolated from the long confirmation delays, and the costs imposed by confirmation delays are shoveled on to the merchants anyway. This is not because a centralized system like Visa requires that design, but rather because they made those choices when providing a product to merchants and consumers. Likewise, others have made similar products with bitcoin. That bitcoin confirmation delays are shorter has no bearing on whether a business can hold funds for 80000 days or whatever you want. This has little to do with suitability for productization. But perhaps this point is too nuanced for "a post that isn't technical".

My own opinion is that I don't really mind whether consumers are "directly" using bitcoin or not. I mean, I certainly don't care if they are manually bitbanging out their own bitcoin transactions or clicking buttons telling software to make transactions. That's a really trivial detail in the scheme of things....

As for being "completely incapable of handling transactions on the volume of the banking system itself", you mention settlement but I don't think you go far enough. Please, tell me the "correct" number of transactions for a civilization such as ours would create daily during normal activity. What is the "right" number and how should it be decided? Should the system exclude the transactions from someone making 100 trillion transactions per minute? What about 1 quadrillion per day? I suspect that this is an unanswerable, totally boring question. Instead, transactions should be based on batching and settlement, which is where the ideas for payment channels is coming from. There's also some recent talk on these lines called "lightning network". More broadly, see http://sourceforge.net/p/bitcoin/mailman/message/33405247/

Some argue that bitcoin is not "wasteful" because there is a real, meaningful use to byzantine agreement. I would recommend https://download.wpsoftware.net/bitcoin/asic-faq.pdf and https://download.wpsoftware.net/bitcoin/pos.pdf and https://download.wpsoftware.net/bitcoin/alts.pdf for some light reading on this subject.

Proof-of-Work (PoW) works because of the economic restriction provided by the second law of thermodynamics. Even though you can't know you're in the consensus set, you can put a raw economic cost on the probability of you being tricked. Bitcoin uses proof-of-work to tie Bitcoin consensus to a fundamentally scarce resource, namely negentropy. It is possible to use another physically scarce resource instead, but there is no alternative to the universal scarcity of negentropy. As maaku puts it, "I could be an AI trapped in a simulation with no knowledge of the outside world other than the foundational laws of physics, and from that be able to assert the validity of proof-of-work.".

As for Stellar and Ripple I would encourage you to read the recent discussion on HN where critical ledger vulnerabilities were enumerated quite thoroughly again: https://news.ycombinator.com/item?id=9341687

"Doing away with banks" has not really been advocated by any of the bitcoin developers. You should perhaps consider the possibility that your sources are lying to you? I don't know, there's no "anti-bank" feature built into bitcoin itself. Anyone can participate on the network, and you seem to agree especially re: why it bothers with Sybil resistance anyway. (As for governance, obv. the project more closely matches the bazaar-style development environment.)

"Does not scale"... well, to be fair, Visa also can't handle 100 quadrillion transactions per second. While the current network is not operating at 10k transactions per second observable by looking at mempools, it may never because of the existence of payment channels. Sorry, folks. (But nobody seems to be complaining about not being able to count the "true" number of users, so..... I suspect that deep-down this is a non-issue). Also check gavinandresen's posts, those were fun.

51% attacks don't do what you think they do. Having lots of hashrate does not mean that consensus rules get thrown out the window. If that was true then the bitcoin network wouldn't have survived its first 12 months.

Hopefully my response has encouraged you (or someone else) to think carefully and critically. I also would like to encourage programmers to look around for the source of knowledge or where it comes from; in bitcoin, the primary sources are going to be the bitcoin source code and whitepaper, and not journalists (because journalists have often not read the source code to find out what's going on).