No actual aliens were discriminated against in the making of this television series.
The message comes across that there are hierarchies of people. Humans First. Then others, who are versions of blacks, Jews, Asians, etc. Culture matters in influencing populations themselves diverse in opinion on race.
You'd think this would have gotten by in the 60's or even 80's, but ENT left the airwaves in 2005.
And frankly, there were those who knew better in 1865. Or earlier. For a sci-fi show supposedly trying to blow your mind with high concepts, this one is as anachronistic as they get. "[Mine] is superior."
What's DSC to bring us? There's a lot of television out there more intelligent, progressive, or cutting edge than anything Treks' done in a while. The world has outpaced Trek.