She (and my grandfather) invested in building in an undeveloped area with their own money. They earned it by working and paying for their house and land.

Now public spenders think she owes them what she spent her life building.

The only world in which grandma cannot afford her LVT is if the value of her land has grown so high that she can make a disproportionately large gain by selling the house. This is very unlikely. And if it is the case, it’s not like the government is stealing her house, they’re just saying she has to realize some of her enormous unrealized gains.