All you can do is make it harder (not impossible, just harder) to openly mention race as a factor in hiring. Three people may decide independently to base their hiring decision on the race of a candidate without ever bringing it up. Hell they might do it without even admitting it to themselves.
Maybe I'm wrong. But if you ever come to Auckland, NZ I could show you a lot of suspicious coincidences.
It's improved since the 50s because racism in hiring was legal then, until we passed a law in the 60s banning it. Social attitudes regarding race have shifted dramatically since 1990 (less than half of Americans approved of mixed race marriages then!), but it's not my impression that this has translated to less racism in hiring than 1990.
We also banned discriminating against older people in the 60s, so it's not clear where to go from here.
Maybe I'm wrong. But if you ever come to Auckland, NZ I could show you a lot of suspicious coincidences.