If all it takes to summon a primal is faith and crystals, and considering the different kinds of beings that Primals are, from elemental gods worshipped by beast tribes such as Ifrit, Titan, Garuda, Leviathan, Ramuh, etc. to figures from folklore and history such as Shiva and Moggle Mog, then what if the truth of the primals is that they're essentially imaginary? In other words, what if the primals don't actually "exist"?

Let me put it this way: if our universe worked in the same way as Hydaelyn does, if aether and crystals were part of our reality, then we could summon primals in the form of gods from all cultures (Zeus, Anubis, Thor), and even as historical, legendary, or folk figures. We could summon Jesus and Santa.

This is because the primals are not "gods" in the traditional sense, but imagination given form through the will of living beings and their aether. God made man in His image, but primals are gods made in Man's (or beastkin's) image.