Not everyone is required to take Astronomy courses in school. For example, my formal education never included it.
> I am really fascinated to see that Milankovic is finally becoming more relevant today. (Ask about a famous Serbian scientist, and everyone can mention Tesla. Ask for the next one, and observe. But that's a good test
While Tesla was ethnically Serbian, I'd consider him to be an American scientist since that's where he lived for most of his life, and did most of his work. Plus he was born in what is today Croatia. Honestly, though, does it really matter other than for fictional nationalistic bragging rights?
> I bring this up in a comment here, and all I get is downvotes
Because you're acting like a snob?
> It's Milanković actually, and that guy also has his own entry on Wikipedia
Had you taken the care to actually read the article you linked, you'd notice that the name of the cycle is Milankovitch, regardless of the actual name of its eponym:
> The second contribution is the explanation of Earth's long-term climate changes caused by changes in the position of the Earth in comparison to the Sun, now known as Milankovitch cycles