I think it depends on what you think of as an average American.Did they actually test for the effects of white/black names, or did they test for the effects of common/strange names?
According to the article, they tested for effects of common names associated with major ethnic groups such as African Americans. They could not have tested for every conceivable minority community in the US, but, if there were a similar effect, it wouldn't have undermined their central finding about the groups they did test for.
The names they used were not common to the average American. Thus this does absolutely nothing to exclude the idea that it's a bias against odd names.
For most people in the US, certain names evoke images of wholesome corn fed all American, often blonde and blue eyed. Kristen, Brett or Brent come to mind. Some names are associated with generations: my firmer workplace hired a woman whose first name was Linda. Her hire was announced a week before we met her and one of my much younger coworkers noted that she must be old: Linda was an old fashioned name associated with the boomer generation. Sure enough, Linda was about 8 years older than I am. Of course, there is the infamous Karen, evoking a privileged white woman of a certain age, with overly done hair. Heidi is a fairly common name among younger (white) women as is Kelly. I knew of zero Liam’s or Ian’s when I was growing up. Now in white middle America, both are common.
In other regions, other names are prevalent and associated with certain groups. People often assumed I was Italian or Catholic or both. Occasionally, going by name only: male. Where I actually grew uo, there were very few Catholics and fewer people of Italian descent.
The average American is still white--white names are far more common than other names. They're also all easy to pronounce.