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Maybe if you assume healthcare stays as-is, you may be able to use roths to keep your taxable-income low enough to stay under the magic number required to get the deductible/max year out of pocket savings and the potentially ~$4000s of dollars a year savings in health care costs.

Numbers:
Hypothetical case: need 30K/year after taxes if getting the MYOP savings or 34K/year after taxes if not and assuming you put in all your money now and wait 30 years to retire using 5% average returns. Assume 4% WR and 27K is the threshold for extra savings. All numbers adjusted for inflation.

t401k:
Need ~213k now -> 921k in 30 years (which would be ~850k after taxes on the gains)
r401k:
Need 193k now if marginal tax rate is 10%, 197k if marginal tax rate is 12% -> 750k (no taxes paid on the gains)
Mixed (you only need to 3k/year from roth to bring taxable income down to threshold):
169K into t401k + 19-20k into r401k (10 and 12% marginal tax rates) = 189k now.

Another easy case is when the current marginal tax is 0%. If you are putting money into retirement accounts when your income is under the standard deduction, then definitely Roth. Traditional literally does nothing in that case.

Of course this is a bit of a contrived example and it assumes you have the same 10-12% marginal tax rate on either side. I think most people who have the extra income to for it to be worth the time to consider the difference probably make enough now to be in higher brackets, but probably will retire with significantly lower spending than their current income. If taxes across brackets increase in the future, otoh, then paying them now would be beneficial and may give some peace of mind about that risk.

There's so many unknowns that I think its a bit oversimplistic to assume one is simply better than the other.

Nope I don't have any examples. You should invest as you see fit, after doing your own research into the options.

It's a gamble basically but I'm gambling that taxes will be higher than the little bit more I might make on gains from the extra pre-tax money.

That will depend on your total savings and such. If you start a 401k at 25 and contribute the max until you retire at 72: you will have a lot of money and it is likely the Roth is better just because because you have so much more taxes to pay. OTOH, if you wait until 45 to start savings and never contribute the max, when you retire at 62 you will do okay (most of your income is from SS - better hope it is still there!) but your total income will be small and so you end up in a lower tax bracket. Odds are you will be somewhere between those two extremes.

Roth and regular investment accounts often have the same annual contribution limits, but the Roth has effectively more growth just because you don't pay taxes: 100,000 in a regular account is worth $70,000 after taxes (exact number depends on your state and tax bracket - it might be $80,000 it might be $50,000), while in the Roth it is $100,000.

There is also the gamble. Nobody knows what tax rates and deductions will be in the future. If things stay the same I can tell you what will happen, but I consider the odds of that zero - but the odds that things are close to today I think are good enough - but I have no way of know. They might make a withdrawals from a Roth taxable (this would go to court, but who knows how the court will look in 30 years). They might change the tax brackets - either up or down. They might make regular retirement withdrawals non-taxable (or taxed at a different rate). They might confiscate all retirement funds in some revolution. Or you might die before you retire. Again I think the safe bet is tax rules will be somewhat close to todays rules, and you will live to the statistical average lifespan plus a couple years - but I do not know.

Traditional IRAs and Roth 401ks are also things.