That's a statement you've inferred from another statement.

You know, it's not a stretch to infer that, from "Well, they get into the gene pool..." when asked about if black people would be okay as a majority society if they would assimilate immediately.

The idea that racial differences in things like success, ability, etc aren't just because of genes (as in, an uneven distribution across races of certain genetic traits), but because of the particular genes associated with the differences in melanin production. In other words, the idea that these positive/negative qualities are inseparable from race.

Okay, so saying that non-white people have worse genes isn't enough huh? Like, you literally have to say "THE BLACKS ARE WORSE BECAUSE THEY HAVE GENES CONNECTED DIRECTLY WITH THEIR RACE." With your definition, not even white nationalists would be considered racist, since they operate under the guise that there are separate "versions" of humanity, and the blacks are just negroids, but they also believe white people with "negroid" heritage are inferior.