We already have estate and property taxation, though. It's not like wealth taxes don't exist, they're just levied at specific times or on specific kinds of assets.

True. Typically property taxes are to fund things at a local level though, and not sent back to the federal government for massive programs.

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...

Uh... your point is about a wealth tax but your facts are about income taxation. In fact, there isn't a whole lot of net "income" reported by the very wealthy, because most of what they make is sheltered investments of various forms. Yet , they have a very large chunk of the total assets owned (like 30% of the country is billionaire assets!), completely disproportionate to the fraction they pay in tax.

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.