Nobody can snap their fingers and change how every country in the globe regulates their businesses though. The basic principle of companies owning other companies is too fundamental to abolish, and if you can create one link then you can make chains and these can be complex. There are no magic wands to solve this, so it's going to take perseverance and hard work, and continuing pressure on politicians.
Making the US the largest tax haven in the world.
* https://fsi.taxjustice.net/en/
* https://en.wikipedia.org/wiki/Financial_Secrecy_Index
Seems that South Dakota is very popular for it:
* https://www.theguardian.com/world/2019/nov/14/the-great-amer...
BTW, that's quite a myth. There were never bank accounts where the banks didn't know who the client was. But not everybody at the banks had access to the info what account belonged to which person.
https://en.wikipedia.org/wiki/Numbered_bank_account
Of course if you as a foreign country could get info about your own citizens having bank accounts is a different question (and that has luckily changed in recent years).
With 911 it became crystal clear that this also obscures monetary flow of deadly criminal actors, deadly at scale and deadly at random targets, 911, Madrid, ...
Wouldn't you think that this would change policies and create a push to more transparency of monetary flow?
Currently the policy values the option of tax evasion at scale higher than the option of controlling in the sense of understanding money flow.