Not just Gen Z. 54% of US adults read below a 6th grade reading level[1][2][3]. The younger generations might skew the results, I haven't dug deep into the links.
I wonder what impact it will have on America's ability to operate over the next few decades. Will a lack of intelligent communicators find themselves unable to coordinate complex business? Even the simplest of enterprises at scale are quite complex.
I expect the end game if it continues is something like Elysium where we're going to bifurcate into a small, literate, educated class, whose parents were able to send them to private schools or overseas to be educated, and who will run the show, and a large underclass who end up as fodder for the corporate machine and/or the war machine. Today, we're in a competitive race to make enough to ensure our great-great-great-grandchildren end up in the first group and not the second.