I realize this is not addressing your point, but it seems that law enforcement and politicians using the term “human trafficking” for everything from prostitution to coyotes helping illegal immigration has done a disservice.
What other term would you like for buying and selling people?
I think the point was that "illegal immigration" is exactly not buying and selling of people, while the coercive/abusive prostitution trafficking pretty much is. And as such, the two things should not share a name. Renaming one or the other would be appropriate now.
But the entire issue is that because the immigration is illegal, there's no way to actually vet the circumstances of the people being transported.
I didn’t think people were including all illegal immigration in human trafficking, but only pointing out that where illegal immigration occurs there is also human trafficking. Illegal prostitution isn’t human trafficking, but they are closely related.
police freely use "human trafficking" to refer to all prostitution. Which is absurd.