Number 2 is definitely not irrelevant for billionaires, perhaps especially for billionaires. Deferring taxes means that your investments can achieve faster compound growth.
Compounding isn't a magic potion that gets you infinitely wealthy though. The highest tax bracket is at < $400k. Over retirement that's a total difference of... say, $10M? We're worried about $10M for someone who has $85B in assets? How much of the $85B do you believe consists of compounding from that $10M?
I literally have no idea what you mean by your numbers. "The highest tax bracket is at < $400k. Over retirement that's a total difference of... say, $10M?" I don't understand this at all.
If you're trying to take advantage of a lower retirement income bracket post-retirement, that's only valuable for < $400k of income/year. Anything after that will be at the highest bracket. Over the course of your post-retirement life that seems to come out to something on the order of $10M in tax savings. Which wouldn't really amount to much for someone with $85B in assets.
It's not only about being in a lower tax bracket in retirement. Tax deferral means that your compounding rate of return will be faster now before you retire, because instead of giving money to the government you can invest it in something that produces a return. I think the section of the article I linked explains it pretty well.
The article does not explain anything. There's no math to back it up either. From what I understand, the difference in the compounding rate of return is actually 0 at all time if you add the liquidation tax liability (which you have to) as a negative value to the net worth graph. The only benefit is that tax brackets (might) go down, which is exactly what people are saying.
More than that: we are talking about stock sales. Long term sales are not part of tax brackets. 18% flat right now, until the law changes. And it can only increase, since we are now in a middle of mad deficit spending. So deferring taxes has it’s own risks.