Ya’ll are thinking about this differently than I do. My concept is diversification — not of asset classes, but of *tax treatment*. Right now, 401(k) and traditional IRAs are treated the same — tax deferred upon contribution, taxed at withdrawal. Both Roth IRAs and Roth 401(k)s are treated the opposite.
I suspect the odds are high that there will continue to be at least these two classes of tax treatment over time for retirement accounts. So no matter how each changes, I am likely to benefit from not having all of my eggs in one tax treatment basket.
So I have a 401(k) with match at work, and a Roth IRA for myself. Two different tax treatments — for someone still decades from retirement. If I were closer, than I might be able to project more accurately what the govmint might do.
So neither is “better”, only “different”. This argument is like the stocks vs. bonds thing, in my eyes.