The rough tax avoidance strategy here is to take out loans with your assets as collateral, and keep rolling those loans forward until you die, at which point they can be paid off and then onto your heirs with relatively little tax. This doesn't give you access to all of your wealth as cash (since the collateral is risky so you need to put up some amount more than you're borrowing), but what you do get you get without paying anywhere near as much tax, the interest on such loans is very low, and you still keep control of whatever asset you're borrowing against and whatever gains/income it might produce.