What I observed is that having FTs per se is not bad... just that the integration process could have been done better. I think for fine-tuning coupled the proper integration process and add that for employers who really cannot find any local that are willing to do the job at same pay only then FT be employed? that seem fair or unfair? of course, the employers will say they must be given the free will to choose.
But social problems exists if everyone is given free will is it not? so somehow there must be a trade-off.