I don't know why you're being downvoted. This is exactly how employers abuse the H1B system.
Give an employer absolute power over an immigrant worker with no connections, support network, or other job options and their residency status on the line--what could possibly go wrong?
To be fair, such an employer usually can't get a H1B these days. Which is probably for the best because those people were probably not completely truthful when they described their tech experience.
There is also an filtering effect on job sites where good jobs get snapped up right away and disappear from the site, while delusional prospects concentrate over time, causing people to think that those sites have nothing but garbage offers.
Give an employer absolute power over an immigrant worker with no connections, support network, or other job options and their residency status on the line--what could possibly go wrong?