system
Given the following post, respond as if you're commenting on Reddit:
human
[Legend of Korra] What changed random non-benders into airbenders?

From everything I've seen, there was no trigger or reason given for why these random people became benders. Supposedly Korra opening the portals created the new airbenders, but that seems like a random/non-sufficient explanation. Did specific spirits do it? What cosmic force was responsible? Was it specifically the portals that caused it, or did the portals just allow something else to affect the physical world?
gpt
Opening the portals was like a pressure release valve releasing spiritual energy back into the world- this is also why plant growth expanded significantly. The influx of spiritual energy remedied issues of balance, in particular, people who had ancestral Airbender blood became conduits for Airbending to return to the world.