A common fantasy trope is that the old gods derived their power from their worshipers, which is why they want temples and ceremonies dedicated to them. In my old Superheroine Battle Arena wrestling site, one of the heroines (and Wonder Woman homage) is Nike, the Greek Goddess of Victory. Who is around in the 21st century because her name is on billboards and sportswear and is in common use. In one scene, she's just sort of wandering around Mount Olympus wondering why she is the last of the Greek gods.