Not necessarily. Communism and the cold war were hot issues in those years, and the idea of a career in the foreign service, the CIA, etc., fueled the interest in Russian. Of course, enthusiasm tended to wane when faced with the actual difficulties of the language.
That said, the tale of Ann and Sr. meeting in a Russian language class is very likely just one more fictional embellishment.
I decided a while back that book was written with a form of "reverse research." Most authors research to make sure at least the broad outline of their remembrances are correct, but the Obama/Ayers duo did the opposite: they would include events and situations that could have occured in that time frame, but ones that were difficult, if not impossible, to trace. Ann's acceptance at UC (the center of Ayers' universe) comes to mind. Universities don't keep application records of non-attendees beyond a minimum number of years, so it was safe to write, 35 years later, that she was accepted there. Ditto the Russian language class meetings -- it could have happened, but getting the transcripts to prove it was highly unlikely.
And it wouldn't take more than one trip to either Kenya or Jakarta to discover the sorry state of their record-keeping. I read an article a while back on the Kenya National Archives in Nairobi -- a bodyguard is recommended. And insects eat school records in Jakarta, of course.
They did overstep on some things though, such as the job at Business International -- but the sockpuppets at the NYT were ever to the rescue, explaining how the book was "full of clever tricks — inventions for literary effect — simply the tricks that art trades in, and out of these tricks is supposed to come our realization of truth." Or, more honestly put, license to lie, with the full blessing of the literati.
Records from Kenya after independence are one thing, but records kept while the British were in charge are quite another. Records kept by the British were moved to the U.K. and if I remember correctly they are stored at Oxford, and the British did keep meticulous records!