Your own suggestion overlooks the unintended consequences of what happens right now. Right now the people become slaves of the companies they work for because

Your own suggestion overlooks the unintended consequences of what happens right now. Right now the people become slaves of the companies they work for because their immigration status is tied to their companies. You think its the option between not getting exploited and getting exploited by the university, but in reality its the option between getting exploited by the companies which sponsor work visa vs getting exploited by the university. Finally, why can't you leave the choice on the people themselves, you're helping the immigrants in anyway by not allowing corporations or universities to be able to hire them easily.