While this has been a more recent development for (Ex) Yugoslavia, nations and nationalism followed a similar pattern elsewhere. You can see a lot of diversity between regions in i.e. Germany, Spain, Italy which is more or less unified by a shared history narrative.

Not arguing it's good or bad. Just saying it's about how and when you define what a nation is.

edit: And to clarify some more, the reason why divisions here are harder is due to the lack of the shared history narrative. :D