There's an alternative for people in high tax brackets: a tax-exempt bond fund. For example, government entities don't tax each other, so when a municipality issues bonds, those are not taxed at the state or Federal level.
Since Traditional IRAs get taxed at ordinary income tax rates - just like bonds in taxable - it does make sense to put bonds there. But also keep to your overall asset allocation: Vanguard's target date funds for those 25+ years from retirement hold 10% bonds.