well uh that would kinda turn the Castlevania lore on its head
I thought the hearts currency stuff is really just a game mechanic sort of thing, not really intended to be some deep thing.
you know its odd that hearts are needed to even use subweapons in the games, and Castlevania doesnt really explain what hearts really are. it always treated itself as a game not to be taken too seriously pretty much.
though yea it can be interpreted in different ways. but I say the townspeople are alive and are what all thats left of humans in that land.