While there could be some synergies in that, there are also questions about potential conflicts of interest such as when, for example, the macroeconomic situation may require a tight monetary policy, but the central bank may demur because such tightening may raise concerns about the stability of the banking system.
Some people argue though that potential conflicts between monetary policy and macroprudential policy are being exaggerated. In entrusting responsibility for macroprudential supervision, and more broadly for financial stability, to central banks, there are concerns also about how this responsibility, might impact the prized autonomy of central banks.