There is no guarantee that any American will be hired to fill any job vacated by a former H-1(b) holder. The firm could contract or fail against foreign competitors.

Guarantees are rare and not a realistic bar for action.

None of this is how this happens though. The reason why companies spend thousands of dollars to pay lawyers is that local talent to do this work simply does not exist. They would much rather prefer hiring Citizens.

I experienced it at my first role after college. I got a job at a hospital as an analyst. Many of my graduating peers applied. Only a few got in. It was odd because the first day the room was divided into two. Literally one side locals and the other side H1B. It’s a group that has less than 1% ethnicity in my area. It was really weird. It felt like there was a quota to hit 50% locals. There were a few experienced people with the software we were using. Most were not and the people that were had a citizenship. That analyst role didn’t even need a CS degree.

This is simply not true, on average. More likely is that they are unwilling to pay the wages that enable the existence of the American middle class.

Americans work hard to have a middle-class lifestyle. Non-Americans work hard just to be Americans.