>>57616169Except they aren't extinct. That's a headcanon that spawned from the anime's dogshit attempt to bundle BDSP and PLA shilling into a single four-part special, but because they weren't actually allowed to have Ash go back in time to Hisui, and they clearly weren't given directives on what to do with the Hisui Pokemon in the modern day by GameFreak and TPC, so they just settled for having them appear in flashbacks while exposition dumping about Hisui during the "traditional Hisui-style festival" that was used as the setting hook for PLA.
SV immediately showed these Pokemon aren't extinct. Perrin has a pair of Hisuian Growlithe, Wild White-Stripe Basculin live in Kitakami, Kleavor can still be found where Black Augurite appears such as Blueberry Academy's Terarium (which also houses Hisuian Qwilfish), and Perrin says that Ursaluna are uncommon Pokemon.
We can thus assume all other species are still fucking around elsewhere, and even if they DID go "extinct", nothing is stopping more spacetime fuckery from happening to allow for those Pokemon to reintegrate into the modern day, just like how fossil Pokemon started becoming an invasive species in Galar because people kept boosting their numbers via fossil revival and breeding, and then released them into the wild.
