Wasn't it just a year or two ago there was supposed to be another "mega batch"?
I feel like with less wildlife to eat them, all the broods are getting bigger.
They evolved for a shit ton of wildlife to eat them before they can reproduce, and we just don't have enough wildlife anymore.
So everytime they come up, more make it back down.
At a certain point, it's going to end up killing a bunch of trees if enough cicadas make it back underground. Especially since they'll be down there drinking tree roots for over a decade.