It means that people with melanin don't pursue careers in Law or Political Science (fields of study that are likely to apply for political internships).
Lawyers with melanin in 2017: 4.28% (
https://www.nalp.org/uploads/2017NAL...USLawFirms.pdf)
APSA Members with melanin in 2017: 3.56% (
http://www.apsanet.org/Portals/54/di...-29-134427-467)
So, if half of that population is Conservative, we should expect to see 2% of Trump interns with melanin. Which is about what we see. I count 1.5/91 people with melanin.
Are you trying to say that Trump is the reason so few people with melanin pursue careers in Law or Political Science?