Of course there is risk in bank deposits, but it is a rather more thorny (and therefore more interesting) topic because the risk is not the purpose of the bank

Of course there is risk in bank deposits, but it is a rather more thorny (and therefore more interesting) topic because the risk is not the purpose of the bank deposit; people generally don't deposit cash with a bank as a means of speculating on the creditworthiness of the bank. A pension fund losing money on stocks is BAU, but a pension fund (or any company) losing bank deposits is exceptional and arguably represents a failure of the market, regulators or both.