I mean there are elaborate schemes to avoid this, but it's not obvious to me that many of them really work short of active (i.e., illegal) tax evasion.

You can, for example, shield stuff in trusts, which is tax-efficient. But when an heir wants to realize gains to buy stuff, it's going to be taxed. All you're doing is deferring, which is fine from the gov's POV as their share of the pool isn't changing, and the pool is in most cases growing a rate that exceeds their borrowing costs.

That said, if Congress wants to make estate/inheritance laws more strict, sure, fine! I think most would be ok with that. Or they could even put a max window on gains realization. But the thing to do there is write an op-ed directly calling for the desired policy, not some sort of alarmist piece about the rich and their "true tax rate".