i think it is that and white fear that their population is dwindling. they will no longer classify mixed people as mixed because they want allies. against what? they have a fear that a minority becoming the majority will do the same to whites that whites did to minorities. they've held this fear since slavery.
White/europeans do have the lowest birth rates in the world (FACT)..but that doesn't matter because they already have the political and economic power here. They control the major institutions in North America and are not gonna loose the wealth they have acquired because they place a lot of importance on things like trans-generational wealth, inheritance, and racial/cultural preservation.
In countries like South Africa, Brazil they are minorities but they still run things.