Just wanna clarify the "change anything and its not vanilla" position:
So suppose they release the Classic servers with no changes at all, all the old bugs and everything still there. If someone finds a new exploit that wasn't discovered in 2004-2007, something that lets say allows them dupe any item or one-shot any raid boss by themselves, would you want Blizz to fix it?
Say they release patches exactly like the did back in the day and don't just have the game run on the last version before the TBC pre-patch. Some of those old patches fixed exploits and bugs, this time everyone will know what the exploits are from the start, should Blizz fix all of those exploits earlier than they did in the past or just let people use them for however long they existed back in Vanilla?
What about addons? If people create new addons that give players access to tools that didn't exist back then should Blizz break the API to prevent that? What about malicious things you used to be able to do with the WoW API like steal all the gold from a character when they went to mail something. I'm not familiar with the Vanilla API so maybe none of the things I mentioned are possible but if they are should Blizz stop it?
If with these kinds of things in mind you still don't want any changes made at all I guess I just wonder why. These sorts of things seem to me like they have the potential to destroy the Vanilla experience as it existed back in 2004-2007 but maybe you see it differently?