No, he's assuming that low performers would have a harder time finding a new job with equal or better pay. Which may or may not be true.
Why would they be looking for a new job if this wasn't a breaking point or final straw for them?
They wouldn't be, which is why I believe this forced return to office action just filters out high-performers who wish to remain remote and it retains almost all of the low/medium skill workers and almost all of the high-skill no preference or work in office preferred high skill workers.
...everyone for whom a full return to the office is a breaking point. You assume that correlates with capability of the employeeto perform their job well.
That does seem reasonable, but it remains just that: an assumption. And you know the thing about assumptions : they make a donkey out of U and MPTIONS.