You just said: "it's not forced''. How can it be deliberate but unforced? People can just refuse to comply to whatever the perceived "policy" is. Like I said, if you are a "White" person in the US, you are free to have as many children as you want, you just can't force other "White" people to. I assume the same is true of any Western government, as things stand.
What existential threat are "White" people facing? Like, what specifically would result in the destruction of the "White" ethnicity? In the long, long term, ethnicities are going to blend out as long as miscegenation is allowed, but that is many generations down the line. My guess is that the definition of "White" will continue to expand and change, as it has in the past, to allow it to be used as an exclusionary category. Given how there are plenty of half-hispanic, self-identifying White Nationalists, my guess is that the "White" ethnic group will start to look more and more...well, ethnic. Much like when Mediterranean ethnic groups were added to be considered "White". I mean, just look at this "white guy":
Ben Franklin mush be rolling in his grave.