Thinking about it, I think we might need better platform rules, maybe even regulations on this. There seems to be pretty much no line of defense, which might explain the rather desperate DoS. If you take anonymity as a right, discussion like ours here on HN are dangerous as well, as they easily make otherwise difficult to find knowledge easily visible. So while a single fan page might go unnoticed, in case of doxing amplification is also a problem. Just my spontaneous thought.
Edit: one afterthought. The story about hacking together a response to the GDPR takedown request quoting press rights and freedom of speech using an LLM shows actually the deeper problem. Actually rights come with obligations (at least ethical ones). At least in Europe press standards are typically rather aware of doxing risks. While actually celebraties also successfully use legal defenses, i still think the defenses for activist are weak balancing interest here (at least if you made something of public interest)