I think that's a good sign. It probably means the problem is being dealt with by admins. Any communities on the affected instances that have subscribers on other instances will be backed up on those other instances, so most of the content is safe no matter what. I just hope the users on those instances know they can come to others in the meantime.
that is really bad because I am one of the moderator for one of the community in that servers. if this spreads out and took longer than expected. I might consider move my community to other servers.
This seems to be a front-end JavaScript exploit, so theres's a good chance that this is a Lemmy problem, not a Lemmy[dot]world problem. Don't be surprised if the issue starts spreading to other instances.
If I were running a server, I would take it offline until a patch is released (Beehaw did this, to be proactive).