Song/Ballad of Oblivion - Bard and Enwalker Ending Speculations (Spoiler Obviously)

[Nekaru_Infitima]

Was this on purpose?

If you do the Bard HW Questline you go on an adventure with 3 NPCs (one a moogle) to discover something known as the 'Ballad of Oblivion.' A song that has the power to bring battles to an end, and later said to be a Coerthan legend of saint in the HEAVENS (space?) who has mastery and can use it to end battles.

Long story short, you find a sealing stone where a fiend that is a harpy siren (bird person) used her voice to do just that, destroy things, and this is the ballad sought.

... Now parallels.
Saint in the HEAVENS.
Bird person.
Literal name of the song.

Did Square just re-use the plot, is Meteion the real harpy it's based off of, did Venat as Hydaelyn let something slip that turned into this legend or ... what is the connection here?