That's a bit of an exaggeration. Many H1-Bs work in high-value industries and make a decent amount of money (I should know, I'm an H1-B holder). I don't think many of them consider themselves slaves.

The green card process for a H1-B is particularly annoying and restrictive though, as is the arbitrary time limit.

Not sure what you mean by "the H1-B visa employee is legally bound to the job". Sure, your company's name is printed on your visa but it is excessively easy to transfer to a new employer.