Perhaps because the senior people were at a higher pay grade? If you bump off the expensive employees, your overhead goes down. Better numbers next quarter so you get a bonus.
Not just senior = higher pay. Senior = more likely to stick to existing (known good) safety/QC processes. Boeing didn't want QC at all - they wanted the guys assembling the planes to do their own QC (which is likely illegal per FAA regulations).
Toss in a side of union busting. And a dessert serving of outsourcing to the lowest bidder, regardless of that bidders history in the space.
Senior people also cost more because their health care costs more. Of course discriminating against older people is illegal, so they cut down on senior staff which just happens to have the same cost reduction. Funny that.
