"fundamentally reshape banking including by sharply increasing liquidity risk for traditional banks." Of course it would, the number of Bitcoins is finite, Central Banks print as much as they want whenever they want. Bitcoin was never supposed to be a part of the Central Banks. "A purely peer-to-peer version of electronic cash would allow online payments to be sent directly from one party to another without going through a financial institution."
The Central Bank does not consider Bitcoin a threat because they plan to implement there own distributed ledger technology.
In an issue of ECBs In Focus they describe three possible scenarios on who should have access to a world wide financial ledger
- indiviual institutions(local banks)
- core players(Central Bank)
- new world(peer-to-peer)
Based on there 'research' they believe the prudent choice is the Central Bank.
By blockchain technology increasing the liquidity risk for TRADITIONAL banks, he is not considering bitcoin here, but implementation of blockchain and cryptocurrencies in banking sector which will make conversion of asset to fiat difficult specially for traditional banks.