There's not a whole lot a GM can do in that case I guess, but I agree telling people to just BList them is pretty useless.
It doesn't make the problem (that person) go away. particularly in cases where worse things happen.

I had someone get into one of my LSs and spam gross/rude/racist things on FFXI, and would log off before anyone could kick them. I reported them 4 times, along with others reporting them, and they weren't even given a temporary ban or anything. All we were told to do was blacklist them.

but how does that solve the problem?
how does that not make the whole linkshell look pretty embarrassing? what if families are playing with their young ones around who they don't want seeing that type of thing?
Things should be done, and I'm also pretty tired of hearing "just black list them lol" cuz it does nothing to help this person stop being a douche to others or infecting any community.