The vast majority of people with money need to get their heads round the fact that they haven't got it through any intrinsic merit, they've just got lucky. It's not something that people want to accept but that doesn't stop it being true and there's a metric shittonne of research to support this.
If a legitimately elected government comes along and wants to redistribute some of that wealth, well then you've just become a bit less lucky than you were before.
Before anyone accuses me of the politics of envy, my beneficiaries will be paying IHT and rightly so.