To be fair, it's only just been featured and hasn't appeared on the front page yet so most of the people taking it that the übernerds of Jetpunkers. Give it a week and I suspect that the number of people getting 100% will drop a lot.
If you don't know history well, it's probably not among the first things that comes to mind for "largest country". Many may not even know it existed pre-Soviet breakup in 1991.
Jetpunkers are übernerds!
probably they ran out of time