@Diptchip I think it's more of a role thing. So smgs are designed for suppression and for firepower at short range whereas pdws are designed to be carried by support personnel for defense. So the original cz scorpion is definitely a pdw even through it's in 32acp. Hell even an m1 carbine fits this description
@Diptchip hey forgotten weapons posted a q&a video this morning making exactly this argument!