Ocasional black person wouldn't be a surprise: there were plenty of Africans in USSR and there is plenty of them in Eastern Europe and Europian part of Russia. But we all know why this guy is in the trailer and is shown in close-up. We do.
What are you talking about? It is the Western Europe that has the largest concentration of black people outside of the United States, not the Eastern Europe:
Also, keep in mind that in the entire United States of America black people consist of 12-15% of the population, which makes France's 8% a staggering amount by comparison. Some of this may be explained by the fact that citizenship was given to children of parents who were part of the former colonies and overseas territories (and France has most colonies in Africa).
Plenty is probably a wrong word. I've been to Eastern Europe before 2022. There were enough blacks for me to see them almost every day. But keep in mind it was big cities, in smaller ones they are probably non-existent, same as in Russia.
I don't know how many of them were actual citizens though. Some of them were tourists perhaps?
Anyway, I'm not here to advocate for putting blacks in everything where they don't belong. I just think a random African in the Zone is not that far fetched.