It works great! We shouldn't be allowing people to avoid taxation, or a wealth tax, by structuring their wealth into illiquid assets, purposefully or accidentally.
How would you have handled taxing commercial/investment property (illiquid asset) from 2006-2012. Do you mark to market? If so, how? How can you do this at scale so the process is fairly applied in all regions, repeatable and trackable?
IANAA(I am not an appraiser), but I'd assume there exists processes to value these assets already. Maybe these processes were gamed in the lead up to 2008, but that doesn't mean safeguards can't be implemented(or not purposely weakened) to prevent this.
Is that your intention?