What's your proposed alternative?
Given that the powers that be clearly have no consensus on the existence of the problem (nevermind that they may have a vested interest in not identifying the problem), and that identifying a problem, while non-trivial, is typically orders of magnitude easier than identifying a solution, it's a little disingenuous to dismiss the point by asking for a solution. Just because the solution is unknown doesn't mean we can't discuss the existence of the problem.
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The sibling comment that asks if the markets are failing more than in the past is more productive because if they are that means that something is different; I personally am disturbed by the degree to which "a rising tide lifts all boats" is no longer true.
I wonder if it's because the wealthy and powerful have gotten better at cornering the market on gains (which would beg for some check on their power), but I also worry that it's actually because material growth has actually stalled, and the market gains are mostly illusion (which would require some other correction).
All this wealth is being generated, but it's going disproportionately (historically speaking) to the wealthy. Well, the problem with that is that the wealthy have an extremely low marginal propensity to consume, so, all they do is invest. That means that both more wealth is available to build businesses and less wealth is available to purchase the resulting products. So, it's easier than ever to create a business because investment dollars are cheaper than ever, but it's harder than ever to make it profitable because nobody's buying. That should depress costs, but the race against inflation has got to catch up eventually. You can keep making it cheaper and cheaper to run a business, but if wages don't increase and cost of living continues to increase just due to inflation, then it doesn't matter how cheap your goods are. There's no middle class left with the money to purchase luxury goods. Then what?
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> Austrian economics doesn't claim that short-term inefficiencies do not exist in markets, but rather that they are less harmful than attempts to fix them.
This seems -- at least partially -- bogus on it's face. Sure, you can definitely regulate a market into collapse (see the Soviet Union) but deregulation can just as easily create supermonopolies which are equally unjust and ineffective. The point of the market isn't to generate wealth, it's to distribute resources efficiently so that the nation as a whole (or state, or world, or whatever collective noun you want to use for human civilization) gets their required products. Generating wealth is a complete side effect of the market as far as the benefits to society are concerned.
This makes a lot of sense, but it doesn't automatically imply unilaterally implementing a wealth tax will solve the problem. It's not like there aren't a lot of people who want to tax wealth rather than income, but it is much harder to hide income than wealth (and yet we still have people who do so to a large degree).
They seem to assume this a priori.
Do you really think ignoring the issue or remaining silent will fix the issue? Do you know what happened historically when wealth distribution and societal demands got wildly out of balance? Crime, famine, revolution, war, and death.