Actual genocides: the Holodomor, the holocaust, Armenian genocide, Cambodian genocide, Rwandan genocide, Srebrenica massacre.
Not a genocide: the slow decline of the white American population as people
choose to have fewer kids due to a greatly reduced child mortality rate and general lack of necessity for additional labor on the ol' family farm.
Definitely not a genocide: the slow decline of the white American population and rise of the mixed-race American population because white women aren't tripping over themselves to have kids with the American equivalent of Japanese 'herbivore men" that spend their days geolocating Shia Lebouf's "He Will Not Divide Us" installations and posting frog cartoons on the internet between futa hentai beat-off sessions and intense philosophical debates about whether or not liking traps makes you gay.