This is my point. They propose a radical new tax that requires measuring people's entire net worth, instead of fixing what's broken using our existing infrastructure which measures forms of income and money flow, because they are clueless, and it's good politics right now. The guy is a self proclaimed socialist, and that means socializing things .
I'm not interested in getting deep into another Sanders argument; looks like he is done. Of course, I'd like to see an inventive, creative, data-driven leader -- think Elon Musk, but without a social media presence. But that'll never happen.
Land value tax in particular seems particularly interesting: if generalised to comprise (almost) all of tax, we can expect a drastic simplification of tax collection, and much less paperwork for everyone when doing all kinds of exchanges, paying an employee, selling goods… at least for unregulated activities. And of course, it would make accumulation of wealth more difficult.
Another route, that several countries have partially and successfully taken, is devoting part of salaries to the common good (tax salaries, at it were): a bit to pay for retirement, a bit to pay for hospitals, a bit to pay for unemployment… this could possibly be generalised to outright communism, where the means of productions are no longer owned by capitalists. (I would avoid a command economy however. We most probably want local stuff to be managed locally. For instance, only people living within 1Km of a bakery should have a say about what the bakery should do, and the people working there should probably decide how they want to work.)
The more pressing problem however is handling the coming recession: as energy (oil, coal & stuff) decreases, so will the GDP (it has already started). I don't know how an "ideal" should look like, but it's certainly not a system that assumes growth that isn't there. I'll just note that without growth, inequalities tend to be much less tolerable.
The new system may be full of bugs, but why would the old system be any better? I've seen old systems. Some of them get their bugs fixed. Many get their bugs worked around, either by the devs, but often by the users themselves: "don't click here, it makes the program crash!"
As for Land Value Tax, do not confuse land with other kinds of wealth. Land doesn't move. Its surface doesn't change. It's market value can change, but it's not wildly fluctuating, like, say, Oil. That makes it much, much easier to tax than whatever property you build on top of it, or goodness forbid whatever precious trinket you might store in that property.
The other proposition, taxing salaries, works today. Taxing more or less salary is just a knob to turn. And at the time such taxes were put in place in France after WW2, the change was swift, and the "new system, full of bugs" worked. Communism (or something close to it) worked, in a Western, democratic country. Okay, it was only applied to school, roads, hospitals, retirement, unemployment insurance, energy… but that's already a pretty big deal, don't you think?
We could "just fix the tax bracket", but then my first reflex would be have a top marginal rate at 100%. I want a limit on maximum individual income. Something like $10M per year to begin with. That may seem ludicrous, to inflict such a brutal end on the American Dream itself. That's it, game over, no one will get rich ever again. But really, that dream is a lie to begin with.
Better yet, we could tether the limit to the median income. Want to get rich? Make your country rich first. That at least should appeal to patriotism, which I believe is still fairly strong in the US.