No. Blizzard never banned MBoxers and there is still a lot of MBoxing in retail.
What Blizzard did was to ban
Input Broadcasting. See it here:
https://worldofwarcraft.com/en-us/ne...sting-software
Therefore ISBoxer has changed its program so multiboxers still can play. The program they are using now is called Joe Multiboxer and is
not using input broadcasting (it is here:
https://joemultiboxer.com/), so there is still a lot of MBoxing in retail and it is
not banable.
Multiboxing is just the fact of been logged in and playing more than one account at the time. When I log on two of my accounts to boost one of my low level in some dungeons, I am multiboxing (even though I move them manually).
Multiboxing has never been banable by blizzard and use of 20 or 30 accounts using an addon not using input broadcasting is perfectly okay.
Scorpyo