A lot of the quitters already had side hustles or are getting into gig economy work. They've already gotten jobs or had planned exits. The assumption of this piece relies heavily on the idea that businesses never expand and that new industries don't emerge.

While it may be true that /some/ people could struggle to find a job, it's unlikely to happen to all of them. And considering that an entire large generation is hitting retirement, there are a lot more jobs opening. Also, given that there is no longer a replacement population being born, there will be a dearth of jobs without replacement people to take them.

I'm certain that some people will be unhappy in work situations where they are forced into laboring for diminished returns over longer work week hours, but that doesn't mean everyone will suffer from it.