Perhaps subscribe to everything you can via email? Won't work for past threads though.
I think the way things are setup by default you get an email pretty much immediately when someone replies to you. So if someone makes a harmful comment as a reply, there's zero chance you won't see it. If it gets flagged and deleted quickly you'll end up being the only one reading it (with the moderators). That'll give everyone else the general impression things are always friendly on the forum.
It's not necessarily a bad thing that nobody sees such messages: 1. it distracts from the topic, and 2. just knowing everyone will read a message about you can be stressful (depending on the nature of the message). But the side effect is that it makes it harder for people in general to realize there's a problem.
I think this is part of the reason the thread about diversity and private groups went so badly (although perhaps not the only reason). Some people applauded a solution for an issue they experienced or knew about. Other people never observed such things and in the (perceived) absence of a concrete problem interpreted it as a political move or some kind of virtue signaling... which of course is very insulting to those affected by the problem ("you're just imagining things" is what it must sound like).
It's hard for everyone to be on the same page on such a topic when we don't get to see the same page. If some people get the full (bad) experience of reading the harassing posts while others only see the post-moderation utopia where all posts are friendly and on-topic, that in itself creates two groups unable to talk to each other about the situation.
Perhaps a naïve suggestion:
If there was a delay to a reply email (say 10-15 minutes), it might give other people a chance at flagging a post before it reached the person being replied to. Someone being targeted might see less of those posts if the rest of the community feel concerned enough to flag them before the email is sent. And we would know a bit more about the content of those posts (I still have have only a faint idea, even after all this discussion). Not sure if Disqus allows that delay. It might have side effects I haven't considered. This isn't meant as a replacement for private groups.
