[Cryptography] What has Bitcoin achieved?

[James A. Donald]

On 2014-06-06 21:19, ianG wrote:
> Bitcoin payments are hugely expensive, it's just that the payer doesn't
> pay that price.  Instead, it's spread across the buyer's fee and an
> inflation tax.  If the system were static, the fees would amount to
> maybe $30-60, about the same as banks internationally.  Part of the
> problem is that the mining rewards are incentivised upwards, a race to
> the most expensive.  When the mining rewards stop there will be
> interesting times/effects, because all that hardware has to be paid for
> somehow.

That seems plausible to me, but I would like to see the basis for that 
estimate.