We are on a technical forum, thus I expect you to come up with a technical description on how can I use fb ads targeting to find out who is white and likes Arsenal in my neighborhood.

Arguing that only some advertisers get access to the tools required is bullshit: this is saying that Facebook won't tell you directly who is such and such, but will give you access to tools to bypass their own rules. I hope you see how idiotic arguing for such a case is.