11 / 15  BIS central bankers' speeches  When one groups the functions of central banks into monetary policy and financial stability policy, central banks’ policy responses since the global financial crisis fall under the heading of financial stability policy if one emphasizes the aspect of addressing systemic risks.
On the other hand, since the financial market is one of the key transmission channels of monetary policy, repairing the impaired market functioning can be deemed part of monetary policy. However, taxonomy does not really matter; the important thing is what is to be done by the central banks, consistent with their mandates.