They really need to expand the lore of fairies. They are creations of a Nymian Empire, attached to the scholar's Soul Stone? Why wouldn't we be able to alter her form? Blah blah lost technology. She is Aether. I'm sure there is a necessary plot hole for it. There always is.

But technically, the smn story line essentially says all primals after ifrit are too strong for you to absorb their aether. Should I think they should break that plot hole and give summoners glamours? Yes. Lore is in the past, it can always be updated as time progresses.