Isn't the main problem with pensions today the dramatic increase in life expectancy post-retirement? They were never intended to support decades of retirement: in the old days, you retired at 65 and there was a good chance you'd be dead by 70, at most 75. (When Social Security was established in the 1930s, life expectancy was only 61.) Nowadays, there's a good chance you'll live beyond 90, with expenses increasing disproportionately towards end-of-life. Combine that with a shrinking birthrate, and no feasible increase in ROI/worker contributions can sustain pension-funded retirements of 25+ years.