It's all thanks to Korra. Avatar Korra. Because of her, airbenders popped up all over the place. [ And then after a short pause she feels she should clarify: ] Not like... you popped up here. Non-benders living here already could just suddenly airbend.

[ Aaaand then she realizes that this is probably a lot to take in within a short amount of time, so she tries to give him a moment. ]