Take in tax on unrealized gains.

Although sadly in nowhere near threshold of the unrealized gains tax, I do wonder what it really means. I know we are only talking about the uber wealthy, who can certainly afford it but I prefer a tax that is not somewhat progressive. Being taxed on unrealized gains would be a killer for normal Americans but if we breach it for the ultra rich, how long before they extend it to the crazy rich, the ultra rich and just the rich? the I feel like taxes need to be written with everything and everybody in mind front the start of this is ever going to work.