I’d think a lot of middle-aged people are looking for the stability of the federal jobs, while the younger people are either unqualified or disinterested in work in general.
I’d also think the affirmative action-based anti-white racism would be a deterrent; the gubmint workforce has minorities heavily over-represented, and they know it is difficult to fire them. Federal workers must deal with a lot of incompetent co-workers, while the private sector has been weeding them out since money got tight.
Which is why the term "Going Postal" was coined.