So I heard a story, from a big business accountant. This is definitely second hand info, and I haven't attempted to google-fu fact check so take this with a grain of salt. But the accountant told me that during our big bank government bailout(s) the government gave the banks the billions they needed, but because the gov couldn't really afford to do that they made a deal to turn around and borrow the same bailout money they just gave the banks at 3%.....
401k/IRA assets can't be confiscated or even abruptly taxed in this manner. Doing so would destroy the assets the government was trying to seize. It can't be done. 401k/IRA assets are totally, fundamentally different than things like government pensions, corporate pensions, social security, or other flavors of state-run old-people-insurance.
Your 401k has risk related to the market and inflation, which the government can influence, but there's no government confiscation risk.