And you do not have to worry about figuring out valuations of a million different kinds of wealth or who owns what. A much simpler formula for taxation, you spend up to $x, tax rate is y%, and so on and so forth.
There was an article on here a few days ago about someone trying to do so and no one at the state tax office could figure out what was actually needed for them to do so.
https://www.cdtfa.ca.gov/taxes-and-fees/use-tax.htm#Overview
From a quick google I think a lot of the additional confusion is the mix of Use/Sales tax when they mostly (as a customer) have the same meaning but for a tax authority have different meaning, searching for "Washington how to declare sales tax" turns up a bunch of random stuff about regulations for retailers showing sales tax correctly, if you search for "Washington how to declare use tax" actually brings up the correct documents from the state, I can def see some bureaucrat not connecting that that's what was actually meant.
It's the same thing with "buyer-reported sales taxes": nice in theory, impossible in practice (note that this isn't a hypothetical: as others have mentioned in the thread, before sales taxes were extended to internet purchases you were supposed to report internet purchases as use taxes, which approximately nobody did).