It's a pretty safe bet that the next 30-40 years is going to explode in entitlements spending and infrastructure costs.
If the government folks don't pay them, then it's going to basically be Mad Max and your IRA (whatever the type) won't really help you much.
If the government folks do pay them, then the money for that has to come from somewhere. It's very unlikely to come from businesses, because the little ones don't make enough and the big ones pay very bright lawyers and accountants to keep the .gov away (cough Apple cough). So, it's probably going to come from income tax.
If you consider the risk of massive tax rate increases over 30-40 years significant, due to the need to pay for massive entitlement and infrastructure spending, also consider the risk that they will tax Roth capital gain withdrawls to pay for it as well.
No, that money would have been in a 401k, so you would lose out on the initial benefit of not having paid taxes when you contributed if they raid Roths.
But, if you've already maxed out your other tax-advantaged space, and you have more money to contribute, there is no reason not to put it in a Roth instead of a regular taxable account, assuming you are eligible, because then you can have tax-free growth at least(worth less than tax-free contributions, but still worth a lot).
In the same scenario that Roth IRAs are at risk of extra taxation (or fees), 401(k)s are as well. That doomsday scenario isn't worth planning for with money, but with physical assets (property, food, tools) and skills because that's the scenario where the US economy collapses (not a recoverable crash like 1929 or 2008, but a true, complete collapse where the USD value goes to zero).
Roth IRAs make sense if you make too much to contribute to a Traditional IRA with tax advantaged contributions and little enough to still qualify for the Roth.
They also (both traditional and roth) have an advantage over a 401(k): You get to manage the funds any way you want. You also get to contribute even when your employer doesn't have one, you just need income (capital gains don't count, as I understand it, so being semi-retired and living off your earnings does preclude you from contributing).
You're also limited on 401(k) investments to whatever your employer contracted for. Could be shitty, could be stellar, you don't control it.
That's what I try to be mindful of regarding Roth. How strong is the promise that it won't be taxed? Or maybe it isn't taxed, but new fees are introduced as a roundabout tax.
Like a lot of retirement thinking, it's unsettling to think about the negative scenarios.
I think it is unlikely, but the chance that they will tax Roth withdrawals is positively correlated with the very scenario that makes contributing to them advantageous, a massive tax hike in the future. If the government needs money that badly, everything is potentially on the table, down to a flat haircut tax on bank balances.
If the government folks don't pay them, then it's going to basically be Mad Max and your IRA (whatever the type) won't really help you much.
If the government folks do pay them, then the money for that has to come from somewhere. It's very unlikely to come from businesses, because the little ones don't make enough and the big ones pay very bright lawyers and accountants to keep the .gov away (cough Apple cough). So, it's probably going to come from income tax.
Get a Roth.