I think there's only two in this forum. Can't remember the other guy's Username though.
There are more Russo fans here. You don't need to have the signature or avatar of someone to be his fan, I am a Undertaker fan but I don't have his picture as avatar.
If there are only 5 users who have Kane in their signature doesn't mean that Kane has only 5 fans here.
Ask people here about their favourite moments or segments in WWE, more than a half will say something from the AE when Russo was the headwriter. They don't need to be his biggest fans but they show with their list of favourite moments and segments that they liked and appreciated Russos work.
As for the filter thing and that Russo was part of a group of writers, try to find some posts from Rock316AE where he posts in-depth how much responsible Russo and Ferrara were during their stint in WWE.