As far as I can tell, the law is not aimed at a "specific subset of migrants"; it is targeting all non-European migrants regardless of their religion, status, public conduct, or attitude towards gender equality. And it is being justified by the exact stereotypes you espoused so strongly in your previous posts: That people from the Middle East, South Asia and Africa are intrinsically misogynist in thought and action, more prone to criminal activity, and harboring a quasi-genetic tendency towards backwardness, savagery, and terrorism.
That is the popular image of people from these regions in the West, and even when presented with evidence to the contrary, the best you get is a mealy-mouthed "well, not all of them are like that, but", with the "but" inevitably segueing back into the aforementioned stereotypes.
I can't think of a mainstream world religion, Western or Eastern, that is not presently strongly homophobic and sexist in its teachings. And even on these very forums, we get, like clockwork, threads full of people bemoaning that gender equality and opposition to homophobia or other forms of bigotry have "gone too far" and must be rolled back at once to whatever glory days of the past currently en vogue, but usually as far back as to make homophobia and blatant misogyny acceptable in public discourse again. And this is a forum housing some of the most open minded people I've met.
So forgive me if I remain highly skeptical of the supposedly intrinsically bigoted nature of West and South Asians, especially when most of these arguments seem to be based on self-reinforcing stereotypes and an enormous helping of selective perception.
I know from second-hand experience that immigrants from Asia and Africa can have enormous difficulties integrating successfully into Western cultural and economic life, but almost none of these problems seemed to come from an inability to accept that women in the West don't wear headscarves and kissing in public is considered acceptable.
I did encounter one young Turk who was a little incredulous to hear that he could, in theory, legally marry his male cousin, but I'm not sure whether that stemmed from homophobia, sexism, some inborn form of bigotry he must have suffered from, or just being a very closeted gay man.