Earlier quoted context omitted.
The features don't matter. What matters is intent and demonstrating that intent. Both the Treasury and Dutch authorities have reason to believe that Tornado Cash was operated with the intent of facilitating money laundering. It's up to a court to determine the veracity of that accusation.
Guilty until proven innocent (they are blacklisted/sanctioned) I see.
In the mean time, yes: the government is allowed to halt activities that it believes are part of an active criminal scheme. Every country with a functioning legal system proscribes this, and establishes a broad swath of controls to ensure that the government can't indefinitely tie up resources.