Bullshit, if you grow up with White people and are used to looking at Whites then any mixed race will look like the other race. Chinese people also think that Eurasians don't look Asian at all and some think that Eurasians look "fully White" because "Asian genes are recessive".
In reality people immediately recognise the other race in whatever races are mixed. The only argument one can make is that blonde hair and blue eyes are recessive but even the vast majority of Whites have brown or darker blonde hair and many Eurasians have this. Blue eyes are the most recessive but it's not like Eurasians have the same eyes as their Asian parents, rather they can have amber or very light brown eyes which are distinctive from either eye colour.
"White genes are recessive" only works if you were raised mostly looking at White people, to Africans mulatto's look more like Whites than we look like other Africans.