This is a common Bitcoin talking point, but it's not a good one.

There are over two billion people in the world who have no bank account or access to even basic financial services; “banking the unbanked” is much discussed in international development circles. Around 2013, Bitcoin advocates started claiming that Bitcoin could help with this problem.

Unfortunately:

* The actual problems that leave people unbanked are the bank being too far away, or bureaucratic barriers to setting up an account when you get there.

* Unless they use an exchange (which would functionally be a bank), they’d need an expensive computer and a reliable Internet connection to hold and update 120 gigabytes of blockchain.

* Bitcoin is way too volatile to be a reliable store of value.

* How do they convert it into local money they can spend?

* 7 transactions per second worldwide total means Bitcoin couldn’t cope with just the banked, let alone the unbanked as well.

* A centralised service similar to M-Pesa (a very popular Kenyan money transfer and finance service for mobile phones) might work, but M-Pesa exists, works and is trusted by its users – and goes a long way toward solving the problems with access to banking that Bitcoin claims to.

Advocates will nevertheless say “but what about the unbanked?” as if Bitcoin is an obvious slam-dunk answer to the problem and nothing else needs to be said. But no viable mechanism to achieve this has ever been put forward.

What subset of those people aren’t using a mobile-based banking system like Mpresa but do have the IT infrastructure to operate a cryptocurrency?

I’m all for helping spread modern infrastructure around but it seems like the current cryptocurrencies are taking on significant overhead to solve problems which aren’t pressing for very many people.

Those millions also need to be well-versed with modern security protocols to keep their cryptosavings from being stolen, and accept the fact that not only the transactions are irreversible (which I guess is okay, considering that neither are Western Union's or Moneygram's), but sending to non-existing null addresses does not return an error, so any typo, a garbled message or a man-in-the-middle attack is also irreversible.

Those people often don't have access to reliable internet or electricity, bitcoin does not solve any of their problems. Further, bitcoin is not spendable money for 95% of human needs, especially in the aforementioned regions. Exchanging bitcoin for spendable money in person is risky, inconvenient and expensive. Bitcoin is a terrible option for this population.