Does asset location even matter if all my money is in tax-advantaged accounts?

No, and this is a common source of over-engineering. Asset location only produces a benefit when you have a mix of account types with different tax treatment, typically a taxable brokerage alongside a traditional and/or Roth account. Inside a single 401(k) or IRA, every asset grows under the same tax rules, so it doesn't matter whether your bonds or stocks sit there; only your overall asset allocation matters. If you're an early-career saver with everything in one Roth IRA, skip the placement puzzle and focus on contributing more and keeping fees low. Asset location becomes worth optimizing once you accumulate meaningful balances across taxable and sheltered accounts.