From the latest blue post, they did.
The thing is and tihis is an example, the seller’s name can be “Séller” and if they get banned they continue the scamming on a new toon called “Sèller”.
This is a huge criminal organisation so banning them daily for only spamming (not scamming if they fail) they’d keep recreating those dummy spammers and Blizzard doesn’t do retroactive chat scanning, they only act on reports it definitely works but the cycle repeats itself mhm.