Who would buy today if there was "panic selling" of financial assets?

We can always imagine a shock ( recession , serious geopolitical crisis , financial crisis ) driving savers to switch to risk -free assets . Investors will then be prompted to sell ( the term "panic selling " is used ) risky assets in order to meet withdrawals from savers , and this selling amplif ies the downward move in risky asset prices . To prevent a complete destabilisation of the price s of these assets , there must be buyers when the ir prices fall . These buyers are no longer banks , given the significant restrictions on the size of proprietary trading. Should central banks then become "buyers of last resort" of risky financial assets? What are the dangers if central banks play this role?