For the people just arriving (post 1970 immigrants), ignoring this history can have little personal cost, atleast in the short term.
For the people that fought for the rights of non-European (Asian, African, South/Central American) immigrants including your Dad, to come here and also fought for the seemingly non-racist present your Dad enjoys, ignoring history is a betrayal of their sacrifices.
This ignorance is also used as a tool to attack their valid claims about extensions of the racist past that leak into the present and their long term losses as the earliest uncompensated investors in the US project.
For the people that fought for the rights of non-European (Asian, African, South/Central American) immigrants including your Dad, to come here and also fought for the seemingly non-racist present your Dad enjoys, ignoring history is a betrayal of their sacrifices.
This ignorance is also used as a tool to attack their valid claims about extensions of the racist past that leak into the present and their long term losses as the earliest uncompensated investors in the US project.