It's very difficult to tell. Employment isn't a finite thing, especially in white collar jobs. High quality workers will generate economic activity which generates new jobs. For ex: imagine a Chinese AI engineer working at OpenAI develops a new tool that generates enough $$ to support a whole team.

How much of that is reality or how much is is suppresses wages will always be hard to pin down.

A basic starting point would be cracking down on H1B mills that explicitly do wage suppression + more scrutiny on big companies like Amazon using it. There's some big H1B consultancies designed to undercut gov contract tending who are much more blatant despite hard rules in H1B meant to stop it. Biden admin passed some new policies to help combat it but enforcement has always been problem #1, not a lack of rules meant to protect American workers.