To address your points:
* Yes, 401k plans usually have high fees, however the tax advantage they provide should more than offset those fees except for the very worst plans. And there are exceptions too: some 401k plans offered by very large companies actually have lower fees than popular low-fee IRA providers.
* When you say "get your money out of your 401k" are you referring to moving it to a low-cost IRA or cashing it out? The former is good advice if you have a 401k from an old job (that is not one of the aforementioned "very good" 401k plans). I don't think there are any reputable financial advisors that would suggest straight-up cashing out a 401k before retirement due to the taxes and penalties. The only circumstance I can think of where that would make sense is if it was necessary to avoid homelessness or pay for necessary medical care and you had already run through your non-retirement savings.
* You absolutely do "own" your money in your 401k as much as you own shares in a brokerage account or deposits in your bank account. If we're at the point where the government would confiscate funds in 401k accounts instead of just issuing new debt then the economy has probably already collapsed to a point beyond recognition.
* Your point about "clueless investment" is a critique of mutual funds and index funds not 401k plans. Someone holding an S&P 500 index fund in their IRA or brokerage account is no smarter than someone holding that fund in their 401k. Additionally, history has shown time and again that the only thing you can say with certainty about the stock market is that its aggregate value increases on average over time. The average person attempting to pick stocks, even at the sector level, is a recipie for them to miss out on the gains they need to have sufficient funds for their retirement.
* Your point about estate and income tax: and having the money in any other form would do what? You need to pay income tax on funds drawn from a (traditional) 401k plan because you deferred the tax when you deposited the funds. Whether you or your heirs are drawing the funds is immaterial in that aspect. If you have funds in a Roth 401k or Roth IRA or a regular brokerage you have already paid the taxes and as such you will not be taxed on withdrawls (except capital gains from brokerage accounts).
Similarly for the estate tax, if you had the money in cash at time of death you would still owe the same amount. On top of that, you'll be dead! What do you care what happens to the money after you're gone? Not to mention you need literal millions of dollars of assets upon death to get hit with the estate tax in the US so this will only apply to the literal 1%.