In The Game in TNG, Picard speaks to Wesley in Latin.
But since the Federation has many species in it, why teach an extinct human language? If one is Vulcan or Betazoid, why give a poo about a dead language from another planet? Isn't it a bit presumptuous to have a dead language from just one of 150 member planets?
Unless it's a course offered only to human cadets, or those from other worlds who apply?