I'm not sure that completely addresses the GP's point, because "mass layoffs" are still somewhat selective. You're more likely to lay off the people that you think aren't worth their pay, which would include those who are already suffering cognitive decline, those who are drinking enough that it's affecting their job performance, and so on.

this paper uses a Bartik / shift-share instrument that looks at changes in sectors and the localized effects (exposure) due to concentration/reliance on that industry. It's an exogenous labor demand shock, not a mass layoff which frames the decision as made at the company level. Skills matter in this consideration but the point is to account for that statistically.

https://en.wikipedia.org/wiki/Timothy_J._Bartik