Earlier quoted context omitted.
I think both stocks and homes should be taxed on realized value. If you sell it, that realizes the value, but also if you use it as collateral, that realizes the value. If you just live in it, we could say that it realizes the amount of rent you would have paid, or that it realizes nothing.
No, the exponential runaway of "rich people get paid for being rich in proportion to how rich they are" is the core problem and focusing on the derivative is a magic trick intended primarily to draw attention away from the core problem. The fact that an earned derivative gets heavily taxed and an unearned derivative gets lightly taxed is so stupendously wacky that the absurdity is obvious, but the integral is the cor…
The fact is that we have no problems with taxing consumption (billionaire buys yacht) but we have an extremely sensible aversion to taxing money spent on productive investment (company pays to build new factory). So business expenses are tax deductions.
The sensible way to handle this is to just use VAT, but then people say "what if they reinvest everything into new ventures and stop buying yachts"? The answer to which is supposed to be "that's what we want them to do". (They also say "consumption taxes are regressive" even though that's easy to fix by giving everyone a large fixed refundable tax credit.)
So to placate them we use something claimed to be an income tax and then push on it until it acts like a consumption tax. Dividends are taxable, but here's a 401k that makes them not while you're of working age and so you only have to pay the tax when you retire and start spending it. Capital gains are taxable, but only when you realize them, so they get deferred as long as you keep them invested in the same company but if you withdraw the money to spend it, that's when you pay. And so on.
This is, of course, dumb, because it makes everything unnecessarily complicated and creates lots of opportunities for tax avoidance, and because it makes the problem you're going to complain about next worse: If they keep reinvesting the money then there is too much economic power in the hands of too few people. But look at what you've wrought. Now if someone invests in a company they get to defer the taxes until they want to spend the money or -- and this is the big problem -- they want to invest it in something else. You have to pay the tax now if you want to do that.
Which means that everybody wants their money to be in some ever-expanding megacorp that allows them to defer the tax until they actually want to spend it, instead of taking the profits from one company and using it to invest in a new one. Which is the thing that wouldn't have been penalized if you were actually using a consumption tax.
And the corporations are actually the problem, not the owners. However much power is concentrated into Microsoft or Apple or Google, that's how much power the CEO of that company will have, regardless of what percentage of the company's stock they own. So you can't fix it by taxing the owners, you have to fix it by making the companies smaller, and that's the thing the existing system makes worse.