This isn't the case. Solvency II treats govt bonds as essentially risk-free, corporate bonds are not treated as risk-free, and there are substantial capital req

This isn't the case. Solvency II treats govt bonds as essentially risk-free, corporate bonds are not treated as risk-free, and there are substantial capital requirements for non-bond investments. UK insurers have substantial holdings of govt debt (really odd that you should get this so wrong), they are one of the largest non-govt investors in the market (obviously).