I agree with your general point, but your specific example of selling highly appreciated real estate is a poor one, since you incur no tax when selling your primary residence (up to something like $500k gain - over your cost basis which includes any capital improvement you made to the property) as long as you lived there for two of the last five years.

It’s a huge tax advantage for homeowners. One could argue that it is in itself unfair as it advantages people who already have large assets over those who do not.