People won't have to pay their taxes if all transactions are untraceable, and therefore will stop doing so.
Without taxation you can't have:
Law enforcement, schools, hospitals, fire departments, roads, road servicing, running water, public transport, welfare, electricity or sanitation.
More directly, you can't have drugs laws, child protection laws or prevent human trafficking, as there's no way to stop the money supply to the perpetrators.
I mean you can probably still get Starlink access for even more astronomical rates, but that's OK because Cryptbros love them some Elon and think all forms of government are encroaching on dem derr freedums.
There's also a coincenter lawsuit on purely constitutional grounds (https://www.coincenter.org/analysis-what-is-and-what-is-not-...).