> virtually impossible to shut down

It has been proven through at least Snowden files that multiple world governments have been working for decades now to operate as many tor nodes as they can in the hopes of decloaking as much traffic as possible, should they need to go after specific people.

I don't think it's safe to say this is virtually impossible. They have more money and resources than you can fathom.

Even if they don't currently have enough nodes to catch a certain person... should it become more important for them to do so, they could always quickly increase that number on short notice to try to increase the chances of tracking them down as needed.