One example they gave, it used to be someone's job to load and unload the silicon wafers into the various etching phases. As time went on more and more of that manual work was replaced with automation. A floor with 50 workers became 25, then 10, then 1.
And, to be clear, this was absolutely a good thing for the product. So many yield issues were caused by manual processes.
The future of any manufacturing is that of high automation. That means low to no jobs. We aren't going back to an economy where a shoe factory employes 500 people.
What's particularly bleak, IMO, is society in the US revolves around work. Every job out there is being automated away. That's not a bad thing for quality, but what it means is there will be increasingly fewer jobs to go around.