Talk about the "ultra-rich" becoming "addicted" to money is loaded nonsense, but never mind.
The idea of taxing investment income leads to a lot of terrible, perverse outcomes. It steers wealth towards being locked up in big companies and funds, since this is how you compound investment fashion without that money being repeatedly taxed. It also makes sure the incentive to invest on one's own accord belongs primarily to capitalists, since the tax naturally compounds when you buy and sell on your own account. Non-capitalists must allocate their money in one of a handful of government-approved fashions, or be eaten by repeated capital gains taxes for things as simple as rebalancing.
Capital gains taxes seem motivated by a broad desire to soak the rich, but you will find very few economists on the left (or the right) supporting this idea over alternatives like a progressive consumption tax. Capital gains taxes are one more example of a clueless "progressive" idea leading to outcomes that are poor to both progressive and non-progressive perspectives.
Lazily posting links without further comment is not really what I think constitutes a good discussion, but I'll bite because I happen to have a link of my own handy.
NPR's Planet Money once brought together a bipartisan panel of economists and asked them what they agree on. Consumption taxes as a replacement for investment+income taxes got universal support: https://nathensmiraculousescape.wordpress.com/2012/08/08/pla...
The effect of a consumption tax would be to never tax investment income until it is spent on something that isn't investment.
Beware Krugman; he is brilliant but sees himself as a pundit in service of a political agenda, and has baldly admitted as much himself. I would be surprised if he disagreed with consumption taxes on grounds other than political expediency. I don't believe that particular question is raised in the posts you link.
You said economists are in agreement on this issue. I showed a prominent economists who isn't. I'm sure I can easily find others. You said that capital gains taxes have terrible consequences, but one of my links shows the history of capital gains taxes in the US, they used to be higher, and terrible things weren't happening.
Your last comment is largely an ad hominem. Consumption taxes are typically regressive.
Edit: your last link did not say what you said it said. It did not say to replace capital gains taxes with a consumption tax. It didn't mention capital gains at all.
Of course, the melange of changes they come up with is self-contradictory: eliminate the mortgage deduction (deducted from income on which you pay income tax), oh, and then eliminate income tax. ditto employer health care plan deductibility, and corporate income tax. i.e.: it's linkbait blogspam of the radio variety.
The idea of taxing investment income leads to a lot of terrible, perverse outcomes. It steers wealth towards being locked up in big companies and funds, since this is how you compound investment fashion without that money being repeatedly taxed. It also makes sure the incentive to invest on one's own accord belongs primarily to capitalists, since the tax naturally compounds when you buy and sell on your own account. Non-capitalists must allocate their money in one of a handful of government-approved fashions, or be eaten by repeated capital gains taxes for things as simple as rebalancing.
Capital gains taxes seem motivated by a broad desire to soak the rich, but you will find very few economists on the left (or the right) supporting this idea over alternatives like a progressive consumption tax. Capital gains taxes are one more example of a clueless "progressive" idea leading to outcomes that are poor to both progressive and non-progressive perspectives.