It's horrible to hear that this has happened.
I guess you're right, but I'd urge people to think twice before sending money to someone they only know via an online forum, no matter their posting history. Ten years ago I was cheated on the Wam - thankfully only to the tune of £5, for a CD. But three or four others were cheated by the same person at the same time, and they lost more than me. The scammer was an established member with lots of posts, who just disappeared off the radar.
He is a long-term member here with over 1000 posts, however. And he sells quite a lot of high end gear - three items this year, at the last count. As far as I can tell, he has never caused a problem on PFM. But the point remains that a history of posting doesn't guarantee honesty.