As someone who has run since Pandaria and missed Pandaria: Remix because of health issues, I can honestly say that they still let people keep those, even if there was a massive call to “roll back” the servers to take those prizes from those that “abused” the bug.
Blizzard could have just as easily let the Druids who got the skins from the bug keep them. Not all of them received every skin (some were missing sparkle kitties, werebears, the PvP skins, etc.). They could have implemented a feature that stopped all future players from making use of the bug instead and simply said: “our blunder. Our fault. We’ll own up to it and let you keep them.” From the sheer amount of people that were made happy from this.
Now, understandably, that would have opened the can of worms of handing out all the Mage Tower skins. And yes, one could make that argument, but Blizzard could simply have communicated that it was, indeed, a blunder. And wouldn’t happen again. But one players shouldn’t have to pay for.
I’m not for that solution either, quite honestly, but it was one that was suggested across several platforms.
I’m not against removing the forms from those that didn’t earn them. I am of the opinion that the Mage Tower should be scaled to retail and allow players to have a chance at it.