In fact some employers will create listings with very specific requirements they have no intention of filling so that they can site it during visa applications.
I actually don't know if this is still a thing, but it was absolutely happening back in the early 2000s. In order to sponsor a TN visa you needed to show several months of trying to find local talent to fill the position. The only proof you actually needed was dated classified ads.
Most employment-based green cards for people already in the country require a fake job listing. If a company is willing to go through the trouble of sponsoring a green card for an existing employee, they are obviously not interested in hiring a replacement. But the government makes them pretend they are, because there are no other ways of keeping the employee.
There are some exceptions, such as EB-1s and tenure-track faculty positions, but fake job ads are the norm.
This reminds me of how things sometimes work in totalitarian states. Some everyday things are effectively impossible to do by the rules. The government does not enforce the rules, because it wants the activity to continue. But when they decide they don't like someone, they can start enforcing selectively and show that the undesirable person is breaking the law.
I actually don't know if this is still a thing, but it was absolutely happening back in the early 2000s. In order to sponsor a TN visa you needed to show several months of trying to find local talent to fill the position. The only proof you actually needed was dated classified ads.
Bad actors always ruin best intentions.