> He pays less next year because Oracle stock is worth less. Just like property taxes on people's houses.

Does he get a refund if he loses money or is it just tax if you win, tax if you lose, tax if it doesn't move?

I'll give a few feelings about property taxes. They are known up front when the purchase is made. There's an expectation that they remain reasonably consistent year over year. In that way they can be consistently planned for, enough that it's seen as more of a maintenance expense for upkeep of local services rather than a wealth tax. If my neighbor sells their comparable property for double what they paid for it a few short years I don't expect my tax bill to have a massive jump. In my experience the city's assessed values tend to lag the true market value pretty significantly. The goal appears to use the assessed value as a means to have some graduated component to the property tax. Being a local tax, any significant jumps are seem to be avoided by design, lest it trigger angry residents showing up at town hall meetings.

With a wealth tax it can be highly variable year to year and out of one's control. If stocks go way up you're on hook for paying those taxes. Especially if you're Larry Ellison with a controlling stake in Oracle, you could find yourself in the situation of having to liquidate assets to pay taxes, thereby reducing your control of your own company.

My main objection to a wealth tax is many of its proponents see it as a means of reducing inequality and "leveling the playing field". I find these positions to come from a place of envy and reject them of those grounds. Many arguing in favor also assume that federal confiscation of wealth inherently benefits the public, as if its some benevolent charity. The reality is more mixed. There is seemingly no limit to politicians' ability squander money on nice sounding projects that give them good headlines while enriching cronies and delivering questionable actual value. It's nice to imagine that all that money is going to roads, bridges, schools, and research, but a whole lot is also going to spying on the populace, subverting foreign governments, and blowing people up.

> With a wealth tax it can be highly variable year to year and out of one's control.

It could be designed to be closer to property tax.

> you could find yourself in the situation of having to liquidate assets to pay taxes

Maybe. There are many other ways: the stock pays enough in dividends to cover the tax, the owner has other sources of income, the owner borrows against the stock to pay tax, and so on. In many dual-class structures the privileged class stock becomes common stock when sold so some founders could maintain control even after selling.

Private companies are trickier but still manageable. I don't want to turn this into a long post though.

> many of its proponents see it as a means of reducing inequality and "leveling the playing field".

I see it as a way to reduce income taxes. Welfare states are currently funded by income and payroll taxes aka taxes on labor. For the math to work out you need higher and higher tax rates or more and more workers. And you're fighting an uphill battle because improving productivity constantly reduces the need for workers.

Instead let improved productivity pay for the welfare state. Stop penalizing people for working by taxing them more.