Acknowledging that the USA has horrible problems with poverty, where wealth inequality superficially appears to be part of the problem, I have the following suggestions:
-Universal healthcare
-Social safety net in terms of indefinite unemployment support and disability pay, so health issues and unlucky upbringing or genetics doesn't lead to destitution and permanently being in the world's shittiest negotiating position. Maybe basic income.
-Finance the above by taxing everyone, including the rich, at a similar percentage as the middle class, designing a tax system that avoids the big loopholes. A wealth tax may be a part of that.
This ensures that lack of wealth doesn't translate into de facto slavery and lack of power over one's autonomy and personal life. It sets a minimum.
I live in Norway, where total taxation is >50% of income on average, we have a 0.85% annual tax on the total value of all assets, capital gains tax is 32%, universal healthcare, de facto basic income system where everyone uncapable of otherwise either get a public-sector administrative job or disability pay.
We have imported the same debate that the author is fronting. This is ludicrous. We don't have a problem with poverty. We have implemented the dream of the American left. Wealth inequality is only a problem if you find it morally problematic in itself. And yet people are still complaining about it.
At that point, it's only about envy and not trying to make the world better.