I’ve always believed that the way it will be done is to further “means test” social security via some sort of asset test. In other words, if you’ve independently saved and have money to retire on other than SS, then your benefit payment will be trimmed.
While not a direct seizure of 401K/IRA funds, the effect is the same.
I agree, and think it's inevitable.
Setting aside the problems with redemption of the "trust fund", once it is exhausted in about 2036 (I think that is the latest estimate), there will only be enough payroll taxes to fund about 75% of the benefits that are expected to be paid under current law.
A relatively simple solution that spreads the pain over everyone would be to simply reduce the cost of living adjustment to Social Security by 1% every year, for the next 20 years or so. But, the Democrats demagogue anyone that even suggests limiting the growth of Social Security payments.
My usual diatribe goes like this: I sacrificed my entire working career, setting aside as much as I was allowed into a 401(k) and/or IRA. I put off buying new cars until the old one was no longer cost-effective, I didn't take expensive vacations, I paid off my mortgage, and I have a nice little nest egg.
On the other hand, my next door neighbor has nearly the same job I do. He has refinanced his house and is mortgaged up to his eyeballs. He buys a new car every couple of years and there's a big boat sitting in his driveway. He is always bragging about his exotic vacations, which are financed on his credit cards -- which are all maxed out. His only liquid asset is the cash in his checking account left over from his last paycheck.
Under means testing, this guy will get all his Social Security benefits. But, since I've been responsible and saving for my retirement, I'll get a reduced (or no) benefit so that he can get all of his.
[BTW, the neighbor I describe above doesn't actually describe any of my neighbors. But, I'm sure you know at least one person like him]
However, this is a lot different than claiming the government is going to confiscate your 401(k) or IRA. That's not going to happen. But, what you described is very likely. If and when it occurs, I have plans to counter it.