I haven’t watched the YouTube video (I generally distrust what Reich says), but here’s what I see from the other sources:

currentafairs

Mentions Buffett once, and only when mentioning the pledge to Gates’ foundation. The article seems to mostly be about the Gates’ foundation taking credit for things they didn’t do. I’ll certainly read through the rest of the article, but it definitely seems to be a criticism of that org, not Warren Buffett.

inequality

Talks about The Giving Pledge (created by Buffett) and how those who have pledged aren’t donating their money fast enough (i.e. their money is growing faster than their donations). I don’t really see this as an issue, since the problem should correct itself when they die.

The article also complains about most donations going to foundations or DAFs, but honestly, when you need to move that much money, that’s probably the most efficient way to do it. So I guess I don’t understand the criticism.

apnews

This one is about wealthy people avoiding taxes generally. I don’t know how this applies to Warren Buffett, whose wealth is in the US and AFAIK isn’t being hidden in tax shelters like offshore banks or trusts. His tax bill is relatively low (this article claims 0.1% from 2014 to 2018), but I think that’s countered by his statements about increasing taxes on the rich (he is registered Democrat, if that matters to you at all).

So I don’t think the issue here has anything to do with Buffett himself, the issue is the tax law doesn’t account for unrealized gains. Or in other words, don’t blame the player, blame the game. The closest Buffett gets to tax shelters is his stock donations to his kids’ foundations, but my understanding is that those are charitable orgs, so I don’t see a ton of difference there vs donating to other orgs like the Bill and Melinda Gates Foundation, which he has donated way more to vs his kids’ orgs.

My personal view here is that any compensation above some amount (say, $400k) regardless of source should be taxed at the current rates, and those assets stepped up in basis appropriately. I don’t like Harris’ proposal though because it’s based on wealth instead of income, but I think Buffet himself would approve a change here. If we handled it that way, the income from stock grants and whatnot for extremely highly compensated employees (like a CEO) would end up being taxed as income (short term gains), and therefore would be functionally equivalent to a cash salary, which is what it’s intending to be.