In my opinion a planet in the Fourth Millennium in which they speak only Italian would break the immersion. Even a planet in which the people speak only English (in the proper sense) would be hilarious : maybe in the next centuries will spread a common human language that will descend, in large measure, from
english, spanish and chinese all togheter, and that kind of 'common human' would be very different from that of the 3100 etc.. even there, the dialect of human communities spread in hundreds of light years across different solar system would differentiate in themselves very soon, leaving a common language as convention.
We assume in game terms that the english (because it's a kind of 'lingua franca') (or the italian if italian players are chatting in game in that moment, or the chinese language between two players that know that, are playing as the human Common Language of the 4th millenium.
Instead, Hypotizing communities or planets that for choices wants to RECONSTRUCT an ancient human nation tradition (it seems similar to the game 'Freelancer' indeed) it can be plausible. In an Italian 'system', the people may have reconstructed some cultural habits of the ancient country, like the art, the architecture and style of buildings (a lot of Reinassance palaces, or ancient Roman building ), a cousine that the Archeologist believes to be more similar to the original Italian cousine of the period ( maybe a more successful reconstruction versus the actual british 'italian cousine'.. that they believes that is Italian, but.. it's BRIT-alian

), and maybe some nice folklore activities like traditional 'Liscio' dancing in the northern emisphere, and the Pizzica and Taranta in the southern emisphere of the planet! ahahah it would be nice but only if COHERENT in the background of Elite Dangerous.
In a case like this, it can be quite possible that actual real italians or italian speakers may go around a planet like this more often, but I don't believe that should become a 'closed space'! I would like very much to entertain me in a Maori Colony Planet, or in a Prussian Styled solar system..
