The gray out users are on your ignore list? I didn't realize it appears like that. I don't have that many people on my ignore list. I thought posts from ignored users simply don't show up or disappear. Like it never existed.
It would be great if it were as you say. But you see at maximum two users; I think no more. And all the rest are their alternative accounts that moderators cannot ban because there is no direct evidence. However, their writing style is very well-defined and has many similarities. This is an example of exactly this kind of behavior when dozens of alternative accounts harm the forum, and maybe it would make sense for them to allow one account per IP.