[polkapolka]

You are thinking too US-centric here. There are jurisdictions where this is allowed.

Also don't stare yourself blind on the numbers.

Do you unfairly deny 5 minorities or erroneously deny 10 genpop?

This is reality for today's data scientists.

Right now in the US: You find an informative variable that acts as a proxy for race (such as Facebook likes). It is not forbidden by law to use it, but you have the data showing the proxy effect. Will you add it to the CTR model and get a raise, or do you act and speak up?

Will you let the trolley follow its course and run over 10.000 Chinese dissidents, or make the switch and run over 100 of your colleagues (and friends) who would benefit from a China expansion?