Also notice that the FBI has no jurisdiction over foreign domains. It happens that the .com (in addition to .us) registry is in the US, but e.g. the .ru registry is in Russia and not under the jurisdiction of US courts.
Unless it's .tv or .to or .me or many others that are administered by organisations under the control of the US. The US seized Telegram's domain t.me by using an "OFAC sanction" whatever that is.