An incel could make the point that the internet changes the calculus, or that "ugly" people can be born to "beautiful" parents, or any other number of counterpoints.

You can't use logic and reason to argue someone out of a conclusion they have arrived at for emotional reasons. Lots of men and boys have been socialized in a really bad way, which makes them unappealing partners. Realizing, accepting, and working to change that, is extremely hard. Instead, with "bad" genetics, then the failures aren't actually your fault, and you don't need to change.