In the spirit of arguing on the internet, I disagree with both of you.
I disagree with Spectral Pontifex (with the quoted part, not the second part) because I definitely do meet Arabs on the streets of Brno with some regularity, but the dudes are usually rather westernized in their looks, just brownish, so it's only obvious with their women in hijabs. An Arab doctor lives two floors below me. Black people are "common" enough that I do meet a couple every day when I walk through the city, there's a ton of Indians and some non-Vietnamese Asians here and there as well. In general cities with universities tend to have foreigners from all areas, though in Brno it's definitely supported by a large tech sector that employs foreigners, so it's more cosmopolitan than the other cities mentioned. But even in Brno when my friend had a black classmate, he was literally being called "black Dave" by his friends because his skin color was by far his most distinct feature (and because he was not a retard who would get offended by that).
That said, thesheep is an obvious retard too lazy to find out the difference between Prague plus a few university cities and the rest of the country. The difference in diversity between Prague or Brno and an average <100k inhabitants town is staggering. It is not uncommon that you would have literally one black dude in a city of 50k that half of the town would know as "the black dude". It is normal that in 20k towns the only people with a non-european ethnicity are a couple Vietnamese people. Czechia outside of cities really is incredibly homogenous. It is quite possible that there are no black people in Kuttenberg today. I certainly did not meet any when I last visited.