unlikely to me that an "Esperanto" would develop such a culture, though not impossible.


True enough, sjm. However, as an example of the possibility, the Nigerians have taken Pidgin - a language developed by the white rulers so that their "servants" could understand enough to serve, but not enough to really know what was going on - and turned it into a very vibrant language, with its own newspapers, books, song-lyrics and slang.