This is not true. The Democratic party has become the party of the ultra-wealthy. Except for Elon Musk and Peter Thiel, how many tech billionaires are Republicans?

Besides, many of these Harris voters do have assets, but they think they're safe because the threshold for this tax would be $100 million. They think their 401k is safe. They're wrong. No tax ever begins by falling on everyone, but eventually, everyone will pay it.

Their stance on this issue (and "tax the rich" more generally) is that they're fundamentallu incapable of conceptualizing second-order effects for any decision. 

 Taxes roll down hill from the wealthy elites to the poor and middle class the rich that vote for Kamala will never pay  the bullshit taxes.  Shit rolls down hill 

Just like the income tax 

 Idk what this means. The wealthy, by a wide margin, pay the most taxes in America. This unrealized gains tax idea would exclusively target that top 1%.

It is certainly possible that these billionaire Harris voters expect some loophole to be introduced that they can use, but as of right now, no such loophole has been proposed (at least publicly).

Your original statement that Harris voters don't have assets to worry about being taxed is just false. The Democrat party is not the same party as it was for the second half of the 20th century.