you are the edge case. for you, it is easy to change employers. For a lot of folks, it is not, despite being equally skilled. it is pretty crass to hand-wave away the real risk of being forced to uproot your life because of the risk that your visa may not be renewed.

About 20% of H1B visas go to indian outsourcing firms. You know the culprits here. Are you really going to argue that these firms are not abusing the system and underpaying employees?