But we can start by not forgiving CG on death. That seems like a no brainer with no downsides.
No downsides I respect, at least. "We want to keep the business in the family" should be ignored.
It's hard. But if we make CG inescapable it should as a second order effect close the Buy Borrow Die loophole, and the super rich must fund their life some other way. Probably by selling assets to consume.
And putting a tamper on inheritance (which could be progressively taxed or capped) it has a second order effect of discouraging hoarding while alive.
So increasing inheritance tax (effectively) would mean a change of incentives for hoarding money. Which is the only thing that actually works.
Obviously, being a hard problem, there's no quick fix. But in the choice between slowing down the problem and not, we should do the former.
How do we "prevent" it? Well, we can throw the baby out with the bathwater. Is that your proposal?
As for your question: no intransigence please.
When Bezos divorced, Mackenzie Bezos was awarded 25% of their Amazon shares valued at over 38 billion dollars.
Just by the above being possible, that means there's no reason why such a "divorce" couldn't happen once per year, and there's also no reason why it has to be 25% rather than "everything above 100M". It means that the tools for this exist. The government takes the place of Mackenzie Bezos. During the divorce, not a single mention of "oh it's just _impossible_ to take 25% of Jeff Bezos' Amazon shares, it will cause collapse". Just all of a sudden if you replace MacKenzie Bezos with "the government" or "the pension fund", suddenly there's all kinds of supposed reasons why it can't happen - even though there's zero reason why it couldn't.
No "but technically they will temporarily have over 100M in the intermediary period" please.
Because it doesn't work that way at that level of wealth, especially for tech CEOs. You can't just hide billions worth of shares in a company.