When people believe that treating all of G-d’s children with equity and in a just manner is a function of good PR or should only be done for our own self-gain, I am deeply turned off and offended.
These sorts of explanations also bothered Rav Soloveitchik and Rav AS Rosenthal and Professor Yeshayahu Leibowitz, among other hakhamim, and I am also bothered by these explanations.
We are duty-bound to treat all people with fairness, kindness, and justice. It is essential to read Talmudic and halakhic texts on gentiles in a manner consonant with our own social and political metziut, not the metziut of yesteryear, which generated racist attitudes in many cases. I recommend reading the writings of Rav Dov Linzer on this.