When Dumbledore is entertaining the possibility that shade!Voldemort possessed Hermione he doesn’t say “But we know that’s not the case because the back of her head isn’t deformed.”
More generally, there’s been lots and lots of specific changes to how magic in general and certain magics in particular work. Forex: in canon there’s no such thing as “magical exhaustion”. Basically everything about Transfiguration is different. Combat is different, and far more detailed.
When Dumbledore is entertaining the possibility that shade!Voldemort possessed Hermione he doesn’t say “But we know that’s not the case because the back of her head isn’t deformed.”
More generally, there’s been lots and lots of specific changes to how magic in general and certain magics in particular work. Forex: in canon there’s no such thing as “magical exhaustion”. Basically everything about Transfiguration is different. Combat is different, and far more detailed.