You are ignoring the most common approach, borrow against the asset. In that case the sufficient assets turn into essentially unlimited untaxed cashflow. Especially with how the market has been lately, the gains erase any burden of the loan. Sounds like a broken tax system to me.
What evidence do you have that people borrow against assets as some tax avoidance strategy? What are the details of this brilliant, often repeated plan? In particular, where do you get interest rates that are low enough to make it worth it to avoid capital gains even with an asset that's grown 100x over its cost basis (and are you accounting for reinvestment of income like dividends that can't indefinitely defer taxes, creating regular tax lots with higher basis that you could sell first)? e.g. are they getting better interest than SOFR somewhere?
So why isn't the suggestion to tax the loan instead of the asset (that is 10x more volatile than say property)?
>into essentially unlimited untaxed cashflow
Loans must be paid back. Loans are cash flow neutral over the maturity. That's why loans are not counted as income.