If you participate in a public event you can’t really expect to keep that activity secret. (One could also argue that the fact you want to indicates you feel there is something wrong about your actions) I wouldn’t really say this is doxing, since that usually refers to revealing a private online identity.
Per the article: people who were not involved in any of the protesting and who hadn't made any statements were falsely named as anti-semites. I'd say thats doxxing - what do you call it?
This is the key reason: doxxing here has the glaringly obvious purpose of harassing the protesters. Nevertheless, while vile and immoral, and double so when it's likely a propaganda operation, it's a risk protesters should be willing to take, along with unlawful use of force. It has been this way historically.