[derefr]

The problem is closer to a ne'er-do-well taking someone else's signs and hanging them off a bridge over a highway. The person producing the speech is having their speech hijacked for malicious purposes by an MITM; that doesn't mean that it's not censorship when the sign's/webpage's creator gets caught in the censorship crossfire during the attempt to take down the malicious actor.

To put it another way: if someone steals my car and uses it to rob a bank, even if that car is now evidence in a criminal investigation, it's still my car. The police have every right to confiscate it from the thief—it's not their car—but that doesn't mean that it suddenly belongs to them; it belongs to me. In both this case and the above case, I have a right to not be unduly punished for the actions of an unrelated third party (by having my website taken down; or by having my car permanently confiscated, respectively.)

The context here is very similar to a story that was on HN just yesterday (https://news.ycombinator.com/item?id=21671579). Banning a site from the internet for happening to be MITMed by China is very similar in its ethical implications to banning a site from the Internet for happening to have a domain-name that fits a pattern used by a botnet.