So how does the fact that HK choose to operate a currency board mean that they have a Central Bank?

They don't have a Central Bank and never have had.

My point, as you well know, is that neither Central Banks nor private banks are necessary intermediaries. Conventional, yes: necessary or even desirable, demonstrably not.

Banking as service provision is a different question.

The financial system cannot be fixed without systemic fiscal reform of a kind which is politically impossible.

Introduction of a complementary financial system is the only solution, and IMHO this will be in place within two to five years.

"The future is already here -- it's just not very evenly distributed" William Gibson