It sucks they lost money. I'm sure some of them are older folks who "aren't all there" and deserve some slack. That said, a fool and their money are soon parted. I especially like the indignation of some of these victims who act as if AirBnB owes them a refund of money they sent a scammer, violating the clear ToS (and basic common sense) to not send money for something via Western Union or wire transfer, especially if you've never met the person.
Some of them are so unbelievably naive -- you got an email from the "host's wife" who tells you instead of booking through AirBnB to click an instant booking link she'll send you, with wire payment instructions to someone completely unrelated, and your first instinct is not to realize this is a scam and stop, not reaching out to AirBnB to see if this is normal, not asking a friend or family member to see if this is normal, but to ASK THE SCAMMER IF THIS IS NORMAL?!? Sure! By the way, that guy with the gloves and mask on who is carrying your TV, laptop, cell phone, camera and stereo out the front door -- he's not an on-call electronics technician doing free service & repairs, he's stealing your shit.