I know some scammers are intelligent people who read a lot and can discover this forum from their research while trying to gather information, but it is possible that some of the people we are referring to the forum are scammers, and we now also have to be careful of the people we refer to Bitcointalk.
I've seen a lot of accounts banned due to fraud, including those from higher ranks as well as beginners. I'm sure that these individuals would have made another account and invited their friends here, so I don't think the problem of scammers is new to this forum.
Where did you see accounts banned due to scam? In this forum, scam is no moderated and I am not sure anyone has been banned because of scam. The punishment of scammers is red tagging and not banning of the accounts.
Talking about Op, some people are not scammers but in the way of life they can change to be scammers. So, how will such a condition be handled, if someone you genuinely introduced to this forum turns scammer.