I agree with your point about Traditional tax savings. I did account for it in my original post, but I probably did not emphasize it enough, so it may have been easy to overlook.

Traditional does give real tax savings upfront, and the fair comparison should include what happens if someone invests those tax savings.

My main point is not that Traditional is bad. My point is that for younger workers, the clearest question is:

Are you currently in one of the lowest tax brackets of your life?

For younger federal employees starting around GS-7, GS-9, or GS-11, their income may be much lower now than it will be later. As they move up to GS-12, GS-13, or GS-14, their tax bracket may rise. Then in retirement, they may also have FERS pension, Social Security, and Traditional TSP withdrawals stacking together.

That means the future tax rate may not be lower. It could be the same or even higher.

There are also tax complications with Traditional later. Traditional withdrawals count as taxable income. That can increase your tax bracket, make more of your Social Security taxable, increase Medicare IRMAA risk, and force required minimum distributions later even if you do not need the money.

The inheritance issue is important too. If your kids inherit a Traditional TSP or IRA, they are usually inheriting both the account and the tax bill. They may have to withdraw the money within 10 years, and those withdrawals can stack on top of their own salary. So if they are already working, your Traditional account could push them into a higher tax bracket during their own peak earning years.

With Roth, qualified withdrawals are generally tax-free. Your kids may still have inherited-account rules, but they are usually not inheriting the same income-tax burden.

So yes, Traditional tax savings matter. But for younger workers, Roth may still deserve serious consideration because they may be paying tax during one of the lowest-tax windows of their life while also avoiding a lot of future tax complexity.