Was the naming thing a reference to William Gibson, or Rumpelstilskin? Is there really a language named after Le Guin? What other references did I miss?
This is a common thing among many fantasy fiction works, so it's hard to tell what inspired it; might not be Eartsea.
Much older. The idea that knowing a being's True Name gives you power over it is common to many human cultures.
There is not actually a language named after Le Guin (at least, not that I know of). However, she did write a fantasy series (Earthsea), in which wizards gain their power from the use of names.