It mentions that wages have been stagnant as proof that it isn't that people aren't applying for jobs that have low pay, but only uses wage statistics as evidence for that, which doesn't really indicate one way or the other that such is the situation.
I think the thing it really misses is the increased conceptualization of open positions that makes it so about the only person in the entire world qualified for a job the way it is posted is either the person that had the job previously, or the exact skills of some other team member.
I assisted in hiring a technical person at a previous job over a decade ago, and after finding no one with the skills we wound up just hiring the most enthusiastic person, and they wound up over achieving.
After harassing HR at my company, I finally made a lateral move where my manager told me he thought at the time of hiring that they needed someone and they thought I might be able scrape by, but now they want me to find someone else just like me.
I've read other studies drawing parallels to online dating and in the face of abundance you keep holding out for something better.
Either people have to do the hard work to generalize the description of the kinds of skills they are looking for that doesn't wind up into yet another set of impossibilities, or the entire hiring process needs a complete reset in some other way. While we're at it we should probably throw degree requirements out the window, and the silly hiring puzzles everyone has been upset about.