Are you assuming that said clauses are coming in with layoffs? All I see is that they are part of a contract on day one, which is where it would make a difference.

In the same sense that it hurts workers if companies cannot (legally) pay them to commit fraud on the company's behalf. Yes, some worker might be paid less because of it, but we're all much better off not allowing the practice.

This is a textbook example of a Prisoners' Dilemma, where we - as a society - are worse off, because the set up exploits the fact it is difficult to coordinate and there's an incentive to break solidarity for one's own benefit.

It is of benefit for all workers to know which abusive companies to avoid.