Ahh yes thank you for pointing that out…this is yet another reason why Blizzard must keep Classic unchanged, or they will risk losing that legal leverage against private servers just like before with retail.
I just had a thought regarding this and wanted to take it a bit further…
I’m willing to bet that we will see an uptick in the number of TBC/Wrath servers once all (or most) of the Vanilla servers are shut down. Something tells me that the private server community will force Blizzard’s hand with putting those out later on down the line as well for the same reason.