It's the absence of pensions for most people that present the most compelling reason to purchase an annuity. But insurers operate in the same universe as other financial companies and the challenges of a zero-interest rate world affect them like everyone else. Furthermore, many insurers are scaling back the contract features that once made variable annuities so attractive and permitted them to perform well during the financial crisis.
The best advice, I guess, is work until 70 and then move to Panama.