Ah, we've reached the great replacement.

No, it is not. Populations naturally evolve, but they never spontaneously evolve to whatever your arbitrary definition of pure white is. Nobody is orchestrating this, and "white" people (quotes because that's quite a moving target) aren't going extinct. Low birth rates aren't replacement, and unless you want to blame our standard of living, they aren't genocide either.

I guess it'd be a more interesting question if you asked who caused the upcoming global climate refugee crisis.