You act like brand new MMOs take beast gaming machines to run.
They don’t.
If WoW got a sequel, it would likely run about how BfA does. They’re not going to suddenly ditch the art style and up hardware recommendations by 2-3x. It would just be a good chance to normalize the graphical quality across the board, as opposed to what we have now which is zones and models and gear ranging from 2007ish to 2020.