Sorry, people with mortgages and children don't quit jobs due to "signaling".

They only quit jobs when they've got the alternative lined up. And they change jobs because the compensation doesn't outweigh the crap.

When a big chunk of your company suddenly walks, that's either high crap or low compensation. And it's been ongoing because they've had time to plan their exit as a group.

The "signaling" just gave them a nice excuse.