IMO Blizzard has always been targeting bots with their changes over the years, and Multiboxing has just been collateral damage. There were some low effort /follow bots in BGs in the past, and blocking that command was their "easy" solution to that problem. The fact that it also broke PvP multiboxing may have been a side benefit, but we will likely never know for sure. Blocking /follow in ALL pvp outside of BGs does seem rather directed at multiboxing, and that aspect of multiboxing has always been one of the most contentious to the non-boxing community.
Blocking software multicasting will definitely kill the fun for many of us, but it also puts a practical upper limit as to how many characters can be utilized at once. Those of us who just want to "play the game" and run our own dungeons should be able to adapt and move on. The "mega boxers" running more than 5 characters are the most affected here. I believe that this was their "easy" solution to getting rid of low effort bots that were using input broadcasting to increase the number of bots they were able to run, by only having one actual "bot" sending the keystrokes to dozens of windows.
I do wish they were able to get rid of the farming bots without affecting us, but it is what it is. I personally already have the spare PCs and monitors, so it's a minimal cost to me to set up a USB multicaster, and redo my macros in game for /follow and /assist, and new keybinds for IWT.
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