They can shut it down so long as they believe the platform is being used by the criminals they hate the most, such as those North Korean hackers, to "launder" money through it.
There
were weapons of mass destruction in Iraq prior to the US invading that country and taking down Saddam, right? Right, guys??
Governments are the biggest liars, the biggest thieves (with banks in second place), and unfortunately since they make the laws and enforce them and instill fear in their citizens' hearts, they get to do whatever the fuck they want to.
I've written letters to my state senators about crypto before. What else can I or any of us who live in the US do? The crypto crackdown is starting to look like it's being run by Joe McCarthy's resurrected corpse.