Pension funds invest in companies and rely on those companies being able to make a steady profit (which the pension funds receive as dividends) so that they can pay pensions. But the current monetary system causes financial instability, which means those returns can be artificially inflated in the short-term but lower overall in the long-term. It also means that the customers of the businesses that pension funds invest in, end up heavily indebted, with little money left over after paying the mortgage to spend in the real economy. So in the long run the current monetary system is bad for pensions. Removing the power of banks to create money would lead to a more stable economy and would be better for pensions.