Sure, not objecting to that. but equating the lack of such bits about every possible country available to "Why won't they let me play as X???" is just silly. I've run a very free form campaign of another RPG set in the interwar era Europe and as a GM I did a lot of reading and "research" into countless different areas, locations, conditions, inventions and technologies throughout that campaign, because I wanted it to be at least tied to reality. Did it make a large difference in the bigger picture? Probably not. Was I happy that at least I knew I put some effort into it? Yes.So, adding in that little tidbit in a short little sentence in the background info for the referee to use as he will can only be a good thing, right? After all, filling in the essential gaps in people's knowledge is what the background is for, isn't it?
For some parties "My character is spanish" might mean that he has spanish written down as a language and that's it.
For others it may mean they looked up the ORBAT, did extended background write-ups and converted a fitting starting weapon from 2e.