The actual lore is literally nonexistent. As you pointed out it would be logically inconsistent for her own world to work in anyway else then the way you mentioned so you can freely interpet that wizards are capable of having whatever physical traits they feel like with magic with such ease that its pointless to even mention it regardless if she as attempted to retcon things via Twitter or not.
This is a world that Rowling created. HRT is up there with the unforgivable curses.
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The actual lore is literally nonexistent. As you pointed out it would be logically inconsistent for her own world to work in anyway else then the way you mentioned so you can freely interpet that wizards are capable of having whatever physical traits they feel like with magic with such ease that its pointless to even mention it regardless if she as attempted to retcon things via Twitter or not.