That is how Trusts already work.
Parents create a Trust. They die. The cap gains in the Trust are zero, and the price basis for the stock (or the asset) is reset to the price of the stock (or the asset) on the day you died.
What this law would do is require your kids - or their Trust - to pay capital gains tax based on the price of the stock (or asset) on the day you bought it.
Among other things, this law would punish investors who buy for the long term.
Also, during your life, you never materially benefited from the increased value of that stock.
During your life you may have received dividends from that stock, but you reported that income and paid tax on it.
True -- but that would apply to capital gains taxes in general on assets held for the long term, regardless of when and how the taxes are paid.