Banks are affected in two ways. One is that when rates are lower, there is an increased customer demand for loans due to the cheaper cost to borrow. The other, is that interest income on the bank's outstanding loans in that it recieves interest on is lower/will decline. Typically, the increased demand for loans outweighs the latter and banks perform better. Additionally, borrowers are less likely to default on their loans when rates are lower which also benefits banks.
Insurance companies benefit from high rates due to their high allocations to fixed income. A sudden decrease in rates could negatively impact profitability. Increasing rates are typically a tailwind for insurance companies while declining rates are a headwind.