I had a job doing a complete reorg of a pretty big company. I studied all the business units, all the jobs, all the RE holdings...basically everything. This company operated out of two huge main buildings and a large number of off-site essentially zombie real estate holdings. The company was so large it had an on-site motorpool and full time pilots. Different types of union jobs in departments that could do anything. It was more or less a small, self-contained city. The company even had its own track rigs and helicopters. Triple digit # of employees at its peak.
It was purchased by another company whose CEO wanted to make it larger. A new company came along with a fraction of employees and no legacy costs and murdered them.
The result? The old company is entirely GONE. The buildings are empty, and they even sold every inch of copper in that place. All those high paying union jobs are gone. Almost ALL the jobs are gone, and all that is left is a few people in a tiny strip office handling paperwork for outsourcing for the out of state main business. Further, most of those jobs weren't replaced with new outsourced jobs, they were replaced with nothing.
At one point, most of these people were useful to the organization. At the drop of a hat, they weren't. I used to live in a tech hub that had a similar story. Hundreds of giant empty buildings that were once full of well paid people. All those jobs now forever gone to China and India.
Hell, I grew up in a boom town. Once businesses started to unwind and downsize, they all did. Boom turned to permanent bust. All those jobs back into the ether from whence they came.