In addition to the soft tax of excessive inflation mentioned by the other poster, Elizabeth Warren and Bernie Sanders have proposed wealth taxes.
https://www.businessinsider.com/wealth-tax-definition-explai...
You can agree with that or not morally, but it is by definition a tax on already legal (and taxed during income) money.
My biggest issue with a wealth tax on the super-wealthy is that it would quickly morph into a wealth tax on everyone above lower-middle class.
Old article but the numbers have scaled proportionately...
"If the IRS grabbed 100 percent of income over $1 million, the take would be just $616 billion. That’s only a third of this year’s deficit. Our national debt would continue to explode." [0]
[0] https://www.forbes.com/sites/danbigman/2012/04/03/john-stoss...
Addressing that discontinuity is exactly what a wealth tax is about. I'm not completely sold on it myself (they're very hard to administer and a giant moral hazard), but don't allow yourself to be fooled into thinking it's a dumb or discredited idea. There's a real problem, and wealth taxes represent a real, if imperfect, solution.