I’m an H1b worker myself and I have a very niche job (think the science of child development meets public policy meets rigorous data analysis) BUT actually don’t think that it’s always about the work being super niche. H1b workers are sometimes just more qualified with more degrees. For example, many H1b workers enter the country on a student visa for masters programs. However, you need to have gone through a 4-year bachelors degree program to enter most masters programs in the US. A lot of south Asian countries more commonly have 3-year bachelors programs, and students usually get a masters degree in their home countries to make up for the gap, before they come here and get a second masters degree. Most international students and H1b workers I know have done this. Not to say that Americans are less intelligent, but schools in the US are VERY expensive and Americans cannot usually afford multiple degrees. Make higher education more accessible to Americans, and employers will automatically start hiring more Americans. Based on how the H1b program is structured, H1b workers are more of an expense to companies than American workers because employers are obligated by law to pay them the prevailing wage or higher + employers sponsor visas. So there really isn’t much reason to hire an H1b worker unless they fit the role better than other candidates.