I'm not sure I agree with everything in this article, but it does make a good point that a lot of the current reporting is decidedly ahistorical. "Record numbers of resignations" don't mean much once you know records were reached in several recent years. What makes this time different? Why the understaffed stores?
(I wrote this) I wish I had clearer answers to those questions! The conclusion is just a little unsatisfying from a writing perspective—it's just too early to tell exactly what's going on. The quits data through most of 2021 don't look all that different from what we'd expect based on the pre-pandemic trend, though there were definitely more than anticipated, especially later in the year. But this is following a massively-disruptive pandemic that put a lot of people out of work and in general had a dramatic impact on the employment situation.
I think the most interesting part is the decrease in layoffs that coincided with the increase in quits. People aren't leaving that much more than before, but when they leave, they're doing so on their own terms.
To me it just looks like it's too early to tell. Did quits go up very quickly in 2021? Sure! But that comes on the heels of a massive spike in layoffs that occurred in 2020. It is at least a possibility that the current situation is a response to that.
One point I didn't go into is the fact that the labor force participation rate also dropped steeply in 2020 and hasn't recovered to pre-pandemic levels yet. So that could create labor shortages that are not necessarily represented in the quits rate.