It's also because an exception to inheritance tax that covers farm land and forests. Rich people have been buying up both (Dyson owns several counties now).
Literally yes - generational farms are expected to go out of business when the head of the family dies as a result, and have to sell up to massive farm businesses.
Excluding any type of income from taxation means every other type of income needs to be taxed at a higher rate, all to protect whatever is being carved out. Thus we tax income from investments, salaries, and yes inheritance.
Inheritance tax has positive externalities as inherited wealth discourages people from being productive members of society. Meanwhile taxing salaries discourages work, and taxing investments discourages savings.
That reductionist analysis treats people as individualised economic drones. What do you mean by "productive" - earning a salary? Contributing to civic society? People don't just do nothing if they have means.
Inheritance tax damages filial peity and encourages the disintegration of society.
> "Inheritance tax shouldn't be a thing in the first place."
The problem with entrenched intergenerational wealth is you eventually end up with a feudalistic society, with a small population of extremely wealthy families controlling all the capital but essentially just becoming rent-seekers, with no incentive or need to innovate in order to maintain their wealth (on the contrary, they will seek to suppress innovation and disruption in order to maintain the status quo). In the long run this leads to violent revolution or other forms of societal collapse.