They want cheap labor
The tech giants want cheap labor so the CEOs receive even larger mega-million annual bonuses on top of their mega-million base compensation. Thus they will do all that they can to dupe the public into believing that allowing more immigrants to take U.S. jobs is a good thing. The unscrupulous CEOs prove everyday that you can in fact fool most of the people, most of the time. There is no shortage of skilled labor in the U.S. contrary to the self-serving claims. The big companies prefer slave labor over paying decent compensation to their employees. This is reality in spite of the dribble disseminated to the populace.