To simplify this; a well know spammer/"almost scammer" has received a flag, and made some negative trust retaliation; which is quite useless, but has also been spamming threads created by people supporting the flag.
Mods have deleted most/all of the spam replies, but that doesn't feel like enough (for many).
Spamming is against the rules and that is why reported spam posts got deleted.
Scams are not moderated and therefore mods wont ban scammers unless they broke some other rules in the process.
Your suggestion of users coming together and 'arranging' for another user to be banned is not the way it should go and is pretty controversial. It is like oppressing a different view on things. The 30 of us 'arrange' for you to get banned because we don't like you even if you didn't break any rules.
Like suchmoon said, if you don't like someone put him on ignore and don't talk to him.
If he is a scammer open a thread in the appropriate section, post all the proof and have him tagged.