You forget that much of the "appreciation" of the assets was accomplished by some sort of "sacrifice" by the individual that started the process, i.e. buying the land or saving the money.
It is funny how the taxers, who are mostly millionaires or better, seem to have enough loopholes in the laws for them to retain their "stuff".
I would like to see a "wealth tax" on Congress, Federal administrators and bureaucrats (including family members) that takes 25% of their net worth every year they are in office or in the position they hold that is financed by the public treasury. Of course you could exempt the first $1 million. Doesn't that make sense as a way to finance the government.