What's the point with that quite lackluster story in Endwalker?

[SDaemon]

Ahhh, I didn't catch that cause/effect. I thought the Aether stagnation was the window the song could get through, but that it was happening naturally.

Hermes gives an explaination after the group fills him in on the Final Days. Essentially because the Song was projected to the Star from outer space its effects were first felt in the locations where the currents were naturally thinnest then just deteriorated things from there.